For Maximum Stability ••• Permalloy Dust Toroids The UTC type HQ permalloy dust toroids are ideal for all audio, carrier and supersonic applications. HQA coils have Q over 100 al 5,000 cycles ... HQB HQA, C, D coils Q over 200 at 4,000 cycles ... HQC ·coils Q over 1 Ji" o;a. x It\-" H;gh. 200 at 30KC ••. HQD coils Q over 200 at 60 KC. The toroid dust core provides very low hum pickup ... excellent stability with voltage change ... negligible inductance change with temperature, etc. Precision adiu,sted to l ¾ tolerance.
lnducta11c• Net Inductance Net Value Type No. Pl'lce Value Type No. Price S mhy. HQA-1 $7.00 70 mhy. HQB-3 $16.00 12.5 mhy. HQA-2 7.00 120 mhy. HQB-4 17.00 20 mhy. HQA-3 7.50 .5 hy. HQB-5 17.00 30 mhy. HQA-4 7.50 1 hy. HQB-6 18.00 50 mhy. HQA-5 8.00 2 hy. HQB-7 19.00 80 mhy. HQA-6 8.00 3.5 hy. HQB-8 20.00 HQB 125 mhy. HQA-7 9.oo 7.5 hy. HQB-9 21.00 2%" L. x 1¾'' x 2½" H. 200 mhy. HQA-8 9.00 12 hy. HQB-10 22.00 w. 300 mhy. HQA-9 10.00 18 hy. IIQl-11 23.00 •5 hy. HQA-10 10.00 25 hy• HQB-12 24.00 • 75 hy. HQA-11 10.00 1 mhy • HQC-1 13.00 1.25 hy. IIQA-12 11.00 2.5 mhy. IIQC-2 13.00 2 hy. HQA-13 11.00 5 mhy. HQC-3 13.00 3 hy. HQA-14 13.00 10 mhy. HQC-4 13.00 5 hy. HQA-15 14.00 20 mhy. IIQC-5 13.00 7.5 hy. HQA-16 15.00 .4 mhy. HQD-1 15.00 10 hy. IIQA-17 16.00 1 mhy. IIQD-2 15.00 15 hy. HQA-18 17.00 2.5 mhy. HQD-3 15.00 UNCASED TOROIDS 10 mhy. HQB-1 16.00 5 mhy. IIQD-4 15.00 (Deduct $1.50 30 mhy. HQB-2 16.00 15 mhy. HQD-5 15.00 for uncased units)
For Maximum Flexlblllty • •• The VIC Variable Inductor The set screw on VIC units permits positive adjust• men! of Inductance to plus 90% minus 50% from rated value. Revolutionary approach for tuned audio circuits. Q and L vs. screw adjustment for a typical coil are illustrated.
Typo Mean list Type Mean Hys. Prlc• Hys. VIC-1 .0085 $11.00 VIC-11 .85 VIC-2 .013 11.00 VIC-1'.l 1.3 VIC-3 .021 11.00 VIC-13 2.2 VIC-4 .034 11.00 VIC-14 3.4 VIC-5 .053 11.00 VIC-15 5.4 l¼" L x 1¼" w. x 1½" H. VIC-6 .084 11.00 VIC-16 8.5 VIC-7 .13 14.00 VIC-17 13 VIC-I .21 14.00 VIC-18 21 VIC-9 .34 14.00 VIC-19 33 VIC-10 .54 14.00 VIC-20 52 VIC-21 83 Y-h•f twin beam power tube with 75 w max CW Input (ICAS), 60 w phone. Compact, rug• ged, a handy-andy for applications-and low• priced! __,_
A LL SUMMER off the air? meter phone, the GL-815- Cathode (:ndirectly Seri.es Parallel heated) r1. No ham likes the idea. two tubes in one-will Filament voltage 12.6 v 6.3 v Vet a large rig isn't prac prove as indispensable an Filament current 0.8 amp 1.6 amp tical in most lakeside or aid as his outboard motor · Avg interelectrode capacitances, shore cottages. Inconven to a fisherman. One GL-815 each of two units: ience and cost are against will handle your final-am Grid-plate (with a high-power transmitter, plifier requirements in push external shielding) 0.2 mmfd plus the handicap of a local pull .•• or ~erve as a Class Input 14 mmfd power source which may AB2 modufa.tor tube .•• or Output 8.5 mmfd be unreliable. act as two single-end driv Frequency at max. ratings 125 me Will a medium-to-low ing stages in your rig. Best Tube Ratings for Typical power rig serve? Yes, for of all, the tube takes full in Operation, Phone (ICAS) those familiar contacts you put with only 400 v on the Plate voltage 400 v Screen voltage 175 v want to keep alive the year plate, meaning you need no Plate current 150 ma 'round. ¥ ou can build such high-voltage power supply. Power output 45 w a rig-economical, simple, And 1since the GL-81 S's small in size-about Type low price sets a real econ • See th d' GL-815, a multi-purpose omy pace for your layout, June H Ne iscussion in M am ews o t ay- twin beam powerv-h-f mar get this saving figure toda_y le~s medivrn-volta : ransformer vel that's shaped to your from your G-E tube distrib Phes ernp/,.,yin 9 f 0 wer sup- 'd gse1 enrum r t"' summer needs. utor!ElectronicsDepartment, • • • 1 eat light ec onets Whether your interest be General Electric Companv, use with Your I ·Weight units for in SO-meter CW or 2½- Schenectad_y 5, New York. c?ttage rig. A~f·P 0 wer summer. d,stributor i Your G-E tube or your free copy.
ELECTRONIC TUBES OF ALL TYPES FOR THE RADIO AMATEUR GENERAL fJ ELECT]!!_~ 1 The Collins 310B-3 band-switching, self its low power source requirement, an ideal rig powered transmitter has a logical place in for emergency service. any ham shack. Collins also offers the 310B-l exciter unit. Designed around the very stable and accu This is identical with the 310B-3 except that rate Collins 70E-8A PTO for use on the 80, it has a link circuit output to work into a final 40, 20, 15, 11 and 10 meter bands, the 310B-3 of higher power. It can also be used as a low starts the beginner in amateur radio with a powered transmitter with an external antenna low investment but with top performance. It coupler. has an antenna network of the universal type Ask your dealer for the Collins exciter which can be connected for either series or bulletin which describes these and other units parallel tuning. It is possible with this antenna at greater length. If you do not have the name tuner to match balanced or unbalanced an of the dealer in your community who is carry tennas as well as a wide range of impedances. ing Collins equipment, we will be glad to Then, if and when he gets the itch for furnish his name and address promptly. higher power, none of his initial investment Net prices to amateurs, complete with tubes needs to be sacrificed. The same 310B-3 will and instruction book, F.O.B. Cedar Rapids, furnish ample excitation for a kilowatt final Iowa: using the new tetrode tubes that are now available. 31 0B-3 Transmitter-Exciter. . . . . $215.00 For the active, experienced ham, the 310B-3 31 0B-1 Exciter...... $190.00 is an excellent standby transmitter, a natural for spot frequency network, and, because of
FOR BEST RESULTS IN AMATEUR RADIO, IT'S ...
COLLINS RADIO COMPANY, Cedar Rapids, Iowa
11 West 42nd Street, New York 18, New York 458 South Spring Street, Los Angeles 13, California
2 JUNE 1948 VOLUME XXXII • NUMBER 6
PUBLISHED, MONTHLY, AS ITS OFFICIAL ORGAN, BY THE AMERICAN RADIO RELAY LEAGUE, INC., AT WEST HARTFORD, CONN., U.S. A.; OFFICIAL ORGAN OF THE INTERNATIONAL AMATEUR RADIO UNION
STAFF Editorial -CONTENTS- KENNETH B. WARNER, WTEH (Managing Secretary, ARRL) Editor "It Seems to Us 9 HAROLD M. McKEAN, WT CEG Feed-Back .•• 10 Auislant Editor GEORGE GRAMMER, WT DF A Detector for Single-Sideband Reception (Technical Director, ARRL) Oswald G. Villard, jr., W6QYT, Technical Editor and David L. Thompson, W6VQB 11 DONALD H, MIX, WlTS BYRON GOODMAN, WTDX Amplifier Instability in Transmitters Assistant Technical Editors Donald H. Mix, WITS 19 EDWARD P. TILTON, WTHDQ V.H.F. Editor A Coaxial-Line Receiver for 220 and 23S Mc. RICHARD M. SMITH, W l FTX Vernon Chambei-s, WlJEQ C. VERNON CHAMBERS, WTJEQ C. 25 JOHN W. PADDON, VE3BLZ Happenings of the Month, Technical Auisfant, 29 ROD NEWKIRK, W9BRD/T 12th ARRL Field Day Coming Up. F. E. Handy, WlBDI 33 DX Editor Coming Conventions , , 34 WALTER E. BRADLEY, WT FWH Technkal Information Service I.A.R.U. News , • • • 36 Production RALPH T. BEAUDIN, Wl SAW A New Approach to Single Sideband Superintendent Donald E. Norgaard, W2KUJ 36 NANCY A. PRICE Assistant When Wires Are Down , • , Albert E. Hayes, jr., WlIIN 43 A Transportable 10-Meter Beam Advertising Emmett P. Bonner, W4MXP 44 F. CHEYNEY BEEKLEY, Wl GS LORENTZ A.MORROW, WTVG I1;1 QST 26 Years Ago This Month ...... • 46 EDGARD. COLLINS Circulation 'Phone-Band Phunnies , , John T. Frye, W9EGV 46 DAVID H. HOUGHTON Circulation Manager The World Above SO Mc. 47 RALPH T. BEAUDIN, WT BA W Hamfest Calendar Sl Assistant Circulation Manager Silent Keys SI ARRL QSL Bureau SI OFFICES Tripling to 420 James W. Brannin, W60VK 62 38 La Salle Road WWV Schedule S4 West Hartford 7, Connecticut Subscrl~lon rate In United l-ltate.s and Preview of DX Contest 'Phone Scores 64 j~ft'bcs1gn;hl3~g~5:u~,f ~~~~!~i~: $5.0U- in all other countriec;:, Hingle How's DX? ••• ... 66 cople.13, 35 cents . .Ei'orehtn rernlttances should be by international postal or express money order or bank draft Surplus Corner - negotiable in the U. S. a.nd .tor un equivalent amount In IJ. S. funds. A "QS-er" for BC-348 Owners 69 lt1ntered as second-cla,c;_is matter l\fuy 61 !t~, 1919. at the post office at llartturd, ARC-S Transmitter Modifications Connecticut. under the Act or !\larch :i 1879. Acceptance tor malling at Fourteenth ARRL Sweepstakes Results 63 sPec.•ial rate or poRtage provided !qr in section 1103, Act ot October 3, 1917, authorized September 9. 1922. Addi Hints and Kinks , . . . • • • 66 t.ional entry at Con_cord, N. H., author ized February 21, 1929, under the Act o! February 28, 1925. Correspondence from Members 67 k~r.r;igt!~4:.br~e ~l~r1~:1~:1~g Operating News • 68 at U. S. Patent Office. Station Activities 78 ·what hallicrafters MODEL HT-18 variable master oscillator does for improved amateur transmission
The HT-18 is called by hams who have used it the most efficient, flexible piece of gear to EASY, PRECISE, FLEXIBLE OPERATION he developed in recent years. Easily added FOR THESE REASONS: to your present transmitter, it brings it right up to date. Narrow band FM and calibrated • Converts any good CW transmitter to a high quality phone transmitter. 5 band V.F.O. complete in one compact cal::ii net with all coils and power supply concen • Eliminates 90 ¾ of broadcast inter ference. trates and simplifies your entire operation. Put your transmitter anywhere, place the • Puts your signal anywhere in the neat, highly functional HT-18 on the operat band with stability comparable to crys tal controlled transmitter. ing table and you're in action. Narrow band FM quality like you've never heard before. • Gives you direct calibration, direct output on all bands 80, 40, 20, 15, The H.T-18 places your signal anywhere in 11, 10. the band with excellent stability. Go to your • Simplifies operation of entire sta nearest Hallicrafters distributor today tion. Puts both frequency selection and for a demonstration and complete technical power control at your finger tips. data on this splendid 72 ohm oµtput. Remote power control instrument . . • • • • $110° 0 terminals. Amateur Net Copyright 19.48, The Hallicrafters Co. haliicrafters RADIO THI HALLICIAFTERS CO. 4401 W. Fifth Ave., Chicago 24, Illinois MANUFACTUIIIS OF IADIO AND ILECTIONIC EQUIPMENT
4 hallicraft MODE-L SX-42 ·
Greatest continuous frequency coverage of any cornmunications receiver-from 540 kc to 110 i\lc in six bands Al\I, Fl\I, CW--with exception ally fine performance on CW. Offers in one rnperbly en{!ineered, precision instrument a top flight ~tandard and VHF communications re• ceiver; standard, short wave and Fl\I broadcast .receiver. Freedom from drift and maximum sta bility are provided by temperature compensa• tion and the use of a type VR-150 voltage regu Continuous frequen'cy lator tube. The tremendous frequency range is made possible by the development of a new coverage from 540 kc ''split-stator" tuning system and to 110 Mc in 6 bands: the use of dual intermediate fre- $27500 AM-FM-CW q uency transformers. ------~------~------MODEL SX-43
The SX-43 provides custom quality, precision ;-ngineering, excellent performance and wide frequency range at a medium price. The SX-43 offers continuous coverage from 540 kc to 55 l\Ic and has an additional band from 88 to 108 l\Ic. Al\[ reception all bands. CW on four lower All the essential bands and Fl\[ on frequencies above 44 Mc. In the band 44 to 55 Mc, wide band Fl\I or narrow a.mateur frequencies band Al\I, just right for narrow $16950 from 540 kc to 108 Mc band .Fl\_[ . reception, is provi ------,---,---,-----,--ATLANTIC DIVISION-,.,..,:,------:----- l<:astern 1:-'ennsylvania ½'31::H~S Jerry Mathis (/l3 Crescent Ave. Glenside Gardens Maryland-Delaware-D.C. \V.3liWT f:.:ppa W. _Darne 132 Tennessee Ave., N.E. \Vm~hington 2, D. C. w~~t~;.~l~~:\j~~key ~❖i~Jf u~~~~Bf_l)(j~~knell ½·1.~V~s'1\~~r::~d Ave. *~~t~ 10 Wf'stern Pennsylvania W,.'!K\VL Eme~.t J. Hlinsky SU9 Beechwood Ave. Farrdl 11------CENTRAL DIVISJON------11 fllinois W9,\ND Wesl~y E~ Marrin.er Q.'1.4 CollPge Ave. Dixon Indiana W9FSG Charles H. Conway 33.35 Colleg,e Ave. (n --.\-l-ab,-a_m_a______--:-:\\ 7'4:-:Gc:-,J:-;\-::V:----"~g.•~Jr::::;~J.EJ~ct?IVIS!1fi-\-~-o-od-c-,-v-ar-dc-B-,ld,-g-.---,-B,-ir_m_i_n_gh_a_m ______1 1 0 W;~::~ 11r;;~~ ~jf)~r, f.~~ieo/M~Il~i~er .:J~~ J-.aif~~ana St, l~~~~~~~l~lle (·~orgia \V4DXI Clay Griffin t557 Athens Aw.- .• S.W. Atlanta West Indies (Cuba-P.R.-V.I.) KP4KD Everett Mal.ver P. n. Box 1061 San Juan 5. P. R. SOUTHWESTERN DIVISIO"',~------;\-,~-fz-~,-,:1-;-e-:-le-,------~:-:~::~:-:k:::O:c~:-L--- 1~~~:0 Santa Barbara l\~fd~~IC~E1tfo\7 \3 rJ!l:~t,;'i;t. Tu<-sou San Diego \V6GC Irvin L. Emig 4.852 Marlborough Drive San Diego 1------:c=::-c-::--:::-:-='--,-,:WEST GULF DIVISION--~. ----~------Northern Texas WSDAS/MNL N. C, Settle 5630 McCornrnas Dalla• Oklahoma \V5HXI B(>rt \VPidner Box 14 Crescent 0 9 st. 1st ~~~h~~foexas ~i~rJ~ f:~~~;;\f\vatsh i~,g_ioxsM~t ri:'A~~:: i ------.,..,.------MARITil\fE DIVISION------Marltlme LNfld. & Lahr. att.) VE!DQ A, M. Crowell 69 Dt1blin St. Halifax, N. S. --,-)-n-ta-r.,.io------:,-::,E=-,3:::.o=u=----:::o=-a~l~r\f1~~hf~~~! s10N-9(_J_W___ el_li_n_~_to_n_R_o_ad----,..L-o_n_do_n_,_u_· n-t-.-- --~------QUEB£C DIVISION------Quebec VE2GL Gordon A. Lynn 1~/u Radio Division, Montreal Airport .Montreal, P. Q. ---c------===:-----:::-;VANALTA DIVISION------1 1 ~~?tiiaColumbia ~~1~§ ~: w•:;1;:o~:es r~g~i~jj~j Ave. {,!:~~~~~~ Alta. Yukon VE8AK \V. R. Williamson Radio Range Sta.• D.O~T. Teslin. Y. T~ ------,-PRAIRIE DlVlSJON ______~-~ ·Manitoba VE4AM A. W. Morley 26 Lennox St. .St. Vital Saskatchewan VE..'iCO Norman Thompson 1120 7th Ave .• N. W. Moose Jaw * Officials appointed to act temporarily in the absence of a rea:ular official. 6 TRADE MARK REGISTERED• U.S. PATENT OFFICE ~made~- FOR ELECTRONIC AND ELECTRICAL USES SOLD ONLY TO MANUFACTURERS AMERICAN LAVA CORPORATION 47TH YEAR OF CERAMIC LEADERSHIP CHATTANOOGA 5, TENNESSEE THE DIRECTORS President GEORGE W. BAILEY ••••...... •••.•. W2KII . . .. 9tl 19th s~. N.W., Washlngton, D. C. Vice-President R.A.D•··1•·0· ..· .. RE .. L.·A.Y··· 0 J. Lllfi~(M~~1ft~t t:c~~.fakiarid ·1ii, ·cai1i.W6EY Canadian General Manager ALEX REID ...... VE2BE 240 Logan Ave., :St. Lambert, P. Q. Alternate: Lennard W. Mltchell ...... VE3AZ ING., 78 Raglan Ave., Toronto. Ont. LEAGUE. •• ··• ...... >•· ·•••····' is Atlantic Division WALTER BRADLEY MARTIN ••...... W3QV the promQtion of interest iii cunafe~r !0~3 Arbutn Rd., Abington, Pa. experimentation, for the rn!oylng...... ,lltemate: ITenry W. Wlckenttlscr. Jr..... W3KWA advancement of the rgdfo J 112 State Ave., Coru.opolls, Pa. Ce'ntral Division CLYDE C. RICHELIEU ...•.•..••.•. W9ARE Marshllcld. Wisconsin Alternate: Harold H. Jansen ...... W0DJG aotn C:a.tifornia Ave., A<\.lton, 111. Dakota Division GOODWIN L. DOSLAND ..•...... •. '\Y0T8)1 Moorhead, ti.nnncsota A.lternate: Robert A. ~imber .•...... \V00L~C Canyon Lake H.tl .. Rapid City, s. D. Delta Division VICTORp'.'t.~~\E:Ji?•. 1'.nke ·,'•iiarles: La.· WSBSR "Of, by and for the ctiriateor," ii numbers withfn its rqnk$ prcti:ii, Alternate: ,James \V. Watkins ...... \V4FLB cally even worth-while amhteur in tlie ricition and has a h,;tdry of ·•· 2:!0 N. flowell 8t .. Chattanooga. Tenn. glorl9us di:hievemerit gs the stor\dard.~beatet in ciin9leur gffciii'$, Great Lakes Division Inquiries reggrdinQ me~beiifiip are ~9lidted: .. i t)OrlCI tide · . HN.;Wt£og: I~~::\~esceni ti,i,e, Pontia.c :i~!~lc?1f.E interesf;n amateur rcidli::ds th111 cmly e~'!¢rtfio\ qiiaHf!cgtiO:n; ii:w6er, }. A:tternate: ,lohn H. Br~hb ...... \VRRPF ihlp of<:i mmsmitting. siC'.l!ion C!08 knawl,t~ge <;if'\fie. eO:de · 1:t,!.l Berl,Rhire Rd., Grosse Pointe Park 30, I\llch. prerectuisite, olthotigh full ·· ·· · ······· ·· · ··· ·· .· grgnted Hudson Division JOSEPII M. ,JOHNSTON ...... W2SOX licensed a11idteurs, ...... A vnn-by-the-~P.a, N, J. Alternate.• Robert A. Kirkmn.n .. , .. , .. , .. '\V2DSY All gertt>ral corresporidenie shi>ulcl b l9In Oak Drive. West l!elmnr. N. J. at the W,st administrative headquarters gt Midwest Division LEONARD r.OJ.LETT., •...... •..• W~DEA Civil 4:cronn.utirs Admfnifrtrntlon Box 776, JQplin, l\Io. Altrrnrae: Alvln 0. Keyf."'!:l ...•••...•... ."\V0I F.D. AND PREPAREDNESS sonal traffic to handle, will • observe better This month there comes what a great many perspective in traffic-handling endeavors than amateurs consider the grandest operating con we have done the last couple of times. It is test of them all, ARRL Field Day. As that natural that great gobs of such personal week-end arrives, several thousand of us will messages should come to us whenever there is t,ake to the field in a combination of outing and a major disaster, but whether or not Aunt practical tests, loaded down with portable Bertha is all right can, should and must wait gear, batteries and gas-engine generators, until the priority traffic of the distressed area tents and fly netting, tools and spare wire, has been handled - until it has arranged for logbooks, swimming suits, hamburgers, lini community medical help, food and shelter. ment - · all the traditional paraphernalia of Experienced amateurs know that what we Field Day. Assuming only that Nature smiles, call "agony traffic" is properly a matter to be a swell time will be had by all. handled only after the critical stage is over, But let us remember that Field Day is some generally only on the second or third day, and thing more than a picnic. We're practising for that the fellows in and around the hot spot emergency communication, perfecting our cannot be bothered about Aunt Bertha right portable apparatus, learning how to succeed then. Yet in some recent emergencies the night in our job when a real emergency comes ------· as has been made hideous by chaps two thousand sooner or later it will. So try to learn some miles away yelling emergency, calling for the lessons from FD and apply them after the channel to be cleared, imploring FCC to come fun is over, particularly in remedying any to the rescue with a declaration - with noth shortcomings of your apparatus. . ing more important on the hook than the The supplying of communication when dis worried inquiry whether Auntie B. is OK. aster strikes our community is one of the ways Let's get perspective on this thing, fellows. in which amateur radio repays society for our Easy does it! Such messages aren't priority operating privileges. It is a duty to be pre traffic. There is no point in getting excited pared to help. Awareness of the importance of over them. Before attempting to shove them emergency preparedness is attested by the into an emergency area it is important to part it plays in ARRL planning and in the know that the first and critical phase of pro expanding membership of our Emergency viding for communitywide relief is over. Only Corps. The League is already in touch, by the thereafter can the personal things be handled. way, with the newly-created Office of Civilian First you must find out by listening - on Defense Planning, with a view to knitting our both c. w. and 'phone - just wha.t the score is. activities into the national needs. We have it Watch the situation, curtail your own trans in mind, too, that our expected new mobile missions, lay off while conditions are critical regulations will considerably facilitate the unless you're a direct participant. To do other tailoring of local communication plans by wise is only to handicap those who have an obviating the need to rely exclusively upon important job to do in the name of all of us. v.h.f. for mobile rigs. The v.h.f. gang is right Emergency procedure in all our nets, by the in there, though, as indicated by recent way, provides for monitoring stations to help progress toward the establishment of a re keep the net frequency clear for urgent traffic, liable 2-meter relay route from Maine to the and so we shall rarely need an FCC order District of Columbia with emphasis on clearing our channels for emergency work. emergency communication. In particular, such a closing order will almost Now, in between emergencies, there is one never be justified purely on behalf of the per thing on which it would be well for us to make sonal-inquiry traffic; let's never ask FCC for a resolution. We propose that we now solemnly one unless the nature of the traffic warrants. resolve that in future emergencies those of us Incidentally, keep it in mind that when a ma outside the emergency zone, with only per- jor emergency exists there are frequent bulle- tins from WlAW with dope on the state of for such frequencies as our 3500- and 7000-kc. FCC orders, best routings to the zone, and bands. Nothing seems to have come of them. pointers on how to help the most and hurt the We're a long way from having the gain on least. those frequencies that we get with beams or So, 0.M . . . when your FD trick is over arrays on the higher frequencies. It would be and you're stretched out on the grass for a spot interesting to have some new thoughts to work of rest, think a little on what's behind the FD on in that field, something we could expect idf,a and plan how you'll conduct yourself in eventually to "reduce to amateur practice" to the next emergency so that you'll make the the further improvement of our communica biggest contribution to assistance and the tion. Has anyone any ideas? biggest addition to the laurels of amateur Lest we preen ourselves a bit too much on radio. our technical progress, however, it needs to be said that we have too many bad signals on the THOUGHTS ON TECHNIQUE air. We understand that FCC took advantage Have you realized that amateur radio tech of our recent DX brawl to do a bit of concen nique didn't gain nearly as much from techni trated monitoring and that they nabbed sev cal developments during the last war as many eral hundred of us for this or that. We would of us had hoped for? It is surprising how little gather that a goodly number of the lads were we got out of it technically. To be sure, there found outside the bands or outside the 'phone is a whole world of startling new techniques subassignments. The rules of the DX contest in the microwaves, and the apparatus to go are so rigidly applied that we doubt very much with them, waiting for us when we wake up to that these cases represented intentional vil them, but so far they have interested only a lainy or unsportsmanlike tactics. We think few of us. We have a vast increase in our these chaps just leaned a little too hard against knowledge of propagation and in the ability the band-edge and that their measuring tech to predict performance. We have much im niques weren't good enough to stand up~ in the provement in tubes, and better components heat of battle. In other words, these cases all around, and the low prices of war surplus represent technical insufficiency in our stations have brought good apparatus to many an or plain poor operating practice under pres amateur who otherwise couldn't afford it. sure. We also understand that some scores of But doesn't it seem that the list stops about t,he boys have recently received FCC greetings there'? Nothing of a revolutionary nature ap on such assorted topics as chirpy notes, inade plicable to our amateur problems has come to quate filtering, spurious emissions including us from the wartime developments, free on a overmodulation products and harmonics, and silver platter. We still get our technical ad key clicks. Of course these are definitely indic vances the hard way, by grubbing them out ative of technical inadequacies in our stations. ourselves in terms of the problems peculiar to The way we see it, all of this means that there congested band-operation. A good prewar h.f. are still lots of things that we need to do in our station is still a pretty good postwar one. If individual shacks to make the heaps behave you take a quick look at the things that are and put out more creditably. new --- such as s.s.s.c., s.s.r., the Q,5-er and • Good thing we never run out of things to all the recent thinking about selectivity· - do, isn't it? Where would the game be if there you'll appreciate that they're adaptations of were no t,echnical problems, no new frontiers'? amateur origin, not wartime military magic. Or contemplate the debate in 2-meter circles on whether vertical or horizontal polarization is superior: it's obvious that it's going to be settled on no war-born scientific knowledge hut strictly as a matter of practical experience. FEED-BACK Upon balance, we think it's better this way. David IL Atkins, coauthor of our March article, It wouldn't be good for our souls to have too "500 Watts of Audio from AB1," advises that C'5 much new magic handed us for free. \Ve learn in Fig. 6 should have a value of 0.01 µfd., not 0.1 more and build our own art more soundly when µfd.; also that one of the three VR-150 regulator our developments come from within. And in tubes of Fig. 3 should be changed to a VR-00 any event, of course, even the most wondrous or VR-105 t,o make the screen potential approxi of new outside concepts. would likely require mately 500 volts. No changes are required in the considerable modification before they could series dropping resistors. be succf,ssfully applied to our specialized A drafting error in Fig. 1 of Paul D. Rockwell's problems. "A Balanced-Modulator N.F.M. Exciter," April But that reminds us: Even though this is (JST, caused the rotor of Sis to be grounded so, we think yearningly of rumors •we heard instead of the switch tap connecting to the lower during the war of improved antenna designs terminal marked "VFO Input." Sorry. 10 OST £or A DetectC?r for Single-Sideband Reception Eliminating the Unwanted Sideband by Phase-Shift Netwoi·ks BY OSWALD G. VILLARD, JR.,* W6QYT, AND DAVID L. THOMPSON,** W6VQB N an earlier paper the basic principles of a.m. 1 and single-sideband detection were reviewed. • \Vc'rc so used to getting our selectivity I- It was pointed out that a change to s.s.s.c. by tuned circuits that it may he startling transmission makes possible a considerable in to most of us to find that there are other crease in the effective selectivity of present-day ways of getting it - maybe better ways. a.m. receivers, whose ability to reject interfering This article describes a single-sideband signals leaves much to be desired. To take full detector circuit that inherently elimi advantage of the benefits of s.s.s.c., a balanced nates the unwanted sideband, entirely independently of the selectivity of the detector (which eliminates interference attribut receiver with which it is used. The ex able to rectification) may be added to existing pcrim~ntal model described here can he ,;ets, and this may be followed by a sharp cut-off sin1plified considerably, as the authors low-pass audio filter for additional selectivity. point out. The only disadvantage of such an arrangement is the audio "image"·-- the audible output pro duced by an incoming radio frequency on the side of the beating oscillator opposite to t,hat of the The method is based on the relatively recent, desired signal. There will be described in this development of simple 90-degree wide-band article a method of eliminating this "image" phase-shift networks.2 A typical network of this which makes possible the design of au inexpensive sort, consisting of 6 reRistors and 6 condensers, is single-sideband receiving attachment for stand capable of dividing a common audio input into ard amateur receivers. The effective-selectivity of t,wo parts whose magnitudes are nearly equal, a receiver equipped with this attachment is sur- and whose relative phases are nearly 90 degrees, over a band of frequencies extending . Common/. F. BALANCED from 300 to 8000 cycles. One of the Input DETECTOR No.I many applications of t,he networks Output mentioned in the referenced article is the generation of single-sideband ra dio signals. It is therefore not sur prising that these same networks may 1------190-DEGREE AUDIO PHASE SHIFT be used in a somewhat analogous man ner to make possible single-sideband reception. A block diagram of the basic system is shown in Fig. 1. Two balanced detectors are connected to a common i.f. input. Oscillator voltage is fed to ~~~~~~::- - OSCILLATOR one dirccUy, and to the other through some means for obtaining a 90-degree r.f. phase Rhift. The Pi~. 1 - Block diagram of single-sideband detector 11,udio output of the second balanced detector is utilizing 90-degree r.f. and a.f. phase shifts. delayed !JO degrees by means of a suitable net passed only by the most elaborate commercial work, and is then combined with that of the other. installations. Single-sideband transmission, plus The method of operation may be visualized this receiving technique, now makes possible for ,with the aid of t,he vector diagra1US of Fig. 2. It is the first time a truly complete utilization of the assumed for simplicity that the incoming signal spectrum available in the amateur 'phone bands is pure c.w. The reasoning is equally valid, how , - something which is hardly possible with con ever, if more than one incoming c.w. signal is ventional a.m. and present-day equipment. present, or if (which is the same thing) the in coming signal is a modulated wave consisting of * Depa.rtmP-nt of Elcct.rical ~~ngineering, ~tanford Uni-. versity, Calif. carrier and sidebands. A vector diagram may be ** Building 202, Stanford Village, Stanford University, likened to a high-speed flash photograph: it is a Calif. way of viewing the situation when all action is 1 0. G. Villard, jr., "8electivity in S.S.S,C. Reception," "stopped." We may tag each a.c. voltage being (JST, April, 1948. 2 R. B. Dome, "Wide-Band Phase-Shift Networks," studied (no matter what its frequency) and Electronics, December, 1946. examine its instantaneous relationship to the Jun~ 1948 11 f Pltase of oscillator input to detector No.1 exactly determined by radio-frequency phase re (A) lationships. Fig. 2-0 represents the audio outputs L.,. Phare ofosci/laior in;iut to detector No.2 of the two detectors plotted as a function of time. 1:'he vertical lines represent the instants in time at which the incoming-signal vector is in phase with the two oscillator voltages, and therefore . (B) will equally well represent the relative phase of is ,..-- Phase of A. F. Ollfput, detector No., the audio output of each detector. It quite ap / ~PltiMeofA.F.outp,!!:,dekdorNo.2 parent that the output of Detector 1 has a phase ~ 9cle o.taudui frquency which is \JO degrees ahead of the output of De I:: tector 2. (C) In E, the counterpart of B, the incoming fre A TIME -- (Ruerenre) quency is higher th.an that of the oscillator, and therefore its vector rotates counterclockwise. rinput todetalorNo.1 Under t,hese conditions this vector becomes (A)n:peated (D) exactly in phase with that of the input to De t:: Oscillator input to tle.tector No. 2 tector 1 after it has become in phase with that of Detector 2. The audio output of Detector 1 now has a phase which is 90 degrees behind that of Detector 2. (E) Now let us suppose that we delay the audio output of Detector 2 by one-quarter cycle, as _.,,.,-- Pltase of A.F. ouiPut, deuclor No. 2 shown in Fig. 1, by means of a 90--degree wide / ,---; Plzase ofA.I: output.detector No. I band audio phase shifter. The output of Detector .f cycle at audi.o fr~uenq b ~:r 2 will wind up one-half cycle behind that of (F) Detector 1 in C of Fig. 2 (i.e., the two voltages A r!ME - ( Referenu) will be 180 degrees out of phase), whereas in F the delayed output of Detector 2 winds up ex Fig. 2 - Vector diagrams illustrating the operation of the single-sideband detector. actly in phase with that of Detector 1. This is the basis on which the sehcme works -- for others. A succession of vector diagrams re c.w. or single-sideband signals lower in frequency sembles a stroboscopic view: If we flash the lamp than the conversion oscillator, the two deteetor in synchronism with one of the a.c. voltages, that outputs cancel; for signals higher in frequency, particular one will appear to be stationary. Volt they add up in phase. By reversing the polarity ages of a frequency slightly higher than our of the oscillator voltages (or that of the detector reference will appear to rotate in one direction, outputs) the detector may be made to respond to while those lower in frequency will ro t.ate in the other. Fig. 2--A is a representation of the rela tive phases of the oscillator voltages be ing fed to Detector 1 and Detector 2. These two voltages will be taken as ref erence - i.e., our stroboscope is flashing at the oscillator frequency and these vec tors will always appear stationary. The vector in B, however, represents an in eoming signal lower in frequency than the oscillator; consequently it would be found to be rotating clockwise if a suc cession of vector diagrams were drawn. This motion is indicated by the curving arrow. It can easily be seen that this rotating vector will B"e parallel to that of the oscillator input to Detector 1 before it becomes parallel to that of the input to Detector 2. We may consider the instant in time at which these vectors are in phase as a reference point in the audio output of Experimental set-up using the single-sideband detector. The separate i.f. oscillator and the two balanced detectors are to the the two detectors, since it is a charac right of the receiver. The chassis housing the 90-degree phase-shift teristic of frequency translation of this networks, the sideband selector switch, and the 6SL7 tube is to the sort that audio phase relationships are right. In the background is the low-pass audio-filter unit. 12 Qst for 6L7 = +B (UPPER OUTPUT) (LOWER OUTPllr) Fig. 3 -·· Simplified schematic diagram of tl:te single sideband detector. Circuits of tl:te phase-shifting net works and the low-pass filter are given in Fig. 4. between the oscillator voltages fed to the two balanced detectors is obtained by means of a coupled tuned circuit. When this circuit is tuned to resonance, the phase of the voltage across it will be found to be 90 degrees from that of the = voltage across the tank circuit to which it is signals either on one side of the beating oscillator coupled. or the other. It will be noted that two 90-degree audio phase shift networks of the type shown in Fig. 4 are Practical Circuits required. The reason for this is that while each Fig. 3 is a simplified schematic showing how network produces two output voltages 90 degrees two balanced detectors, two 90-degree phase apart in phase, the relative phase of these two shift networks, and a low-pass filter may be voltages bears no fixed relationship to that of the combined to make up a single-sideband detector. input voltage. Therefore two identical networks The circuits of the phase-shift networks and of the must be used in order to get the necessary 90- low-pass filter are shown in J?ig. 4. A complete degree audio delay between the outputs of the schematic of the entire unit is given in Fig. 5,. two detectors. Fig. 6 gives vector diagrams illus This unit is by no means the best way to carry trating the action. A c.w. input signal is assumed; out the functions indicated in the block diagrams therefore the audio output is sinusoidal. In A, - it merely represents a first experimental model the relative phase of the audio output of·the first whose only merit is that it does work! It is hoped balanced detector is shown. This is split into that it will serve, however, to illustrate the prin two portions, 90 degrees apart in phase, but bear ciples involved. ing no fixed phase relationship with the input Referring to .Fig. 3, the 90-degree phase shift voltage. It is assumed that at the particular • •if· Top view of the balanced detector chassis. The i.f. toning control for r.f. phase shifting is brought out to the front by means of a flexible shaft. The large knob is the oscillator tnning control. • • I June 1948 I audio frequency chosen for the example, the cuits, 8 no comment is peeded here, other than phase shift between input and output happens that filters of this type are now commercially to be that shown. Fig. 6--B shows the output of available. Since the phase-shifting networks are t.he second balanced detector, and it will be seen good up to 3000 cycles, a filter cut-off frequency that the upper output voltage of Network 1 is of 2500 cycles may seem unnecessarily low; how of just the right phase to cancel the lower output ever, it is found to be perfectly satisfactory in of Network 2. 0 and D show how the situation practice from the standpoint of intelligibility, and is reversed when the incoming signal is on the gives greater effective selectivity. other side of the oscillator frequency. Fig. 5 looks quite a bit more complicated than Two other characteristics of the phase-shifting Fig. 3, but most of the extra details are circuit networks should be mentioned. It will be ob components added for the sake of convenience in served that each requires a push-pull input; this is the experimental model. Much could have been essential for their correct operation. The output cut out if economy had been the primary con impedance of the two networks is very hlgb, and sideration. · Coupling to the last i.f. stage of a as a result it does not appear to be possible to standard communications receiver (in our case connect them in series or in parallel without up a National NC-200) is accomplished by means of setting their normal operation. For thls reason their outputs are combined in the 6SL7 twin 0-3S4h1J. 0.3S4hlj. triode. The "sideband selecting switch" in Fig. 3 makes it possible to listen to c.w. and s.s.s.c. signals either higher or lower than the oscillator frequency, the others being rejected. The reason for this can be seen by following through the vec tor diagrams of Fig. 6. LOW-PASS FILTER 2SOO·CYCLE Cl/T·OFF Notes on Circuit Details Construction of the phase-shift network of Fig. 4 offers only one difficulty. The values ac t,ually used should be as close to those shown as possible. It has been found that reasonably good performance is obtained if the values are matched to within plus or minus 5%; but the closer the match, the better the network may be expected to perform. Since t,he condensers and resistors most commonly used have a tolerance of the order of plus or minus 10%, it is very desirable to check the actual values on both resistance and c.Jl.pacity bridges. Most well-equipped radio serv ice shops have both types, and the job of picking • Fig. ,J - The low-pass !ilter and wide-band phase values elose to the desired is not an especially shift network. Tn the phase-shift network the valnes shown should be matched as closely as possible. The tedious task when a large assortment is avail filter coils msed in the experimental unit shown use No. able. 25 s.c.c. enamel wire scramble-wound on wooden spools II picking items from an assortment is too 1% inches in diameter and 2 inches between sides. The time-consuming, an alternative method is to 0.354-hcnry coils have 1.74 pounds of wire each, the 0.258-henry coils l.5 pounds, and the 0.035-henry coil measure a oondenser or resistor accurately (no 0.64 pound. The sides of the spools are 4¾ inches in matter what its value, provided it is less than diameter. that desired) and then parallel or series it with additional units whose rated values make up the a 6C4 cathode-follower tube built into a plug-in difference. The error will then be small. As an adapter. The second detector of the receiver fa example, suppose one wanted to make up a removed, the adapter containing the 6C4 plugged 0.00535-,ufd. condenser. A 0.005 is picked from in, and then the detector tube mplugged into the the box, which when measured is found actually adapter. The 604 derives its filament and plate to be 0.00510. This may be paralleled with a currents (which are negligible) from the receiver, 0.00025 10% tolerance condenser to give 0.00535 and provides a low-impedance i.f. output of sev plus or minus 0.2%. eral volts for connection to the single-sideband The low-pass filter shown in Fig. 4 happens to be an experimental unit left over from another I W. W. Smith, "Premodulation Speech Clipping and job, and its description is included here merely fur Filtering," QST, February, 1946; W.W. Smith, "More on the sake of completeness. It is fairly easy to make. Speech Clipping," QST, March, 1947; J. W. Smith and N. H. Hale, "Let's Not Overmodulate," QST, November, Since the design of such filters has been widely l946; Galin, "Audio Filters for the Speech Amplifier," discussed in connection with speech-clipping cir- (JST, November, 1947. 14 QST for detector. The grid of the 604 connects to the grids of the 6L7s. Connected to the plates of each secondary of the last i.f. transformer, the other pair of 6L7s is a small step-down transformer of side of which is grounded. Addition of the 604 the Class AB driver type (turns ratio primary to necessitatel!l only a very slight retuning of the ;Hi secondary = 3:1). The step-down is needed i.f transformer to restore perfect alignment. to provide a low source impeda:nce with which to The i.f. signal from the 604 is attenuated by feed the networks. To prevent resonances in the means of a small variable condenser to approxi transformers, swamping re. (1 h :;;< .,0 ~ '----...,t,..------'l'--r------1'-'1'=,-----'1'"'---t-Oi5 ~ (0+ I- ~ ,------s.., 'Q' ~•u ~"' I 'I I L June 1948 15 variable resistors connected across the trans strong a.m. signal with the oscillator detuned. former secondaries may be adjusted to equalize The cathode resistors are then adjusted for mini the outputs of the two detectors so that complete mum audio output. cancellation can take place when the correct If the phase-shift networks have been con phase relationships exist. structed with accurately-measured components, The oscillator was made push-pull, although it they may be relied upon to operate as planned. could equally well have been single-ended. Both To test them, only a variable-frequency audio balanced detectors require oscillator voltages of oscillator and an oscilloscope are required. For opposite phase, however. A 6SJ7 buffer tube is best results, the networks should be fed from the used between the oscillator and the phase-shifting oscillator via a push-pull audio tra.nsformer of coupled circuit, in order to prevent any reaction fairly good quality, preferably of the step-down on the frequency of the oscillator caused by variety. The horizontal and vertical amplifiers of tuning the secondary of the phase-shifting i.f. the oscilloscope are then connected to the two transformer. (By connecting the coupled circuit network output terminals, and the relative gains to the plate of an electron-coupled oscillator, it adjusted until the pattern becomes as nearly would have been possible to eliminate the buffer circular as possible. The audio frequency may tube while still providing isolation between this then be varied from 300 to 3000 cycles; if the circuit and the oscillator tank.) The 6SJ7 is not pattern remains approximately circular over this required to produce any gain; therefore its input range, the network is functioning properly. It is from the oscillator is cut down by use of a small important that both networks behave as nearly ,~oupling condenser. Resistance loading of the i.f. alike as possible. Actually, even if the network tI·,msformer secondary can also be used to reduce design values are duplicated exactly, the patterns the g--aln and has the advantage that the circuit will not remain precisely circular over the range Q is thereby reduced, making the tuning less because in a simple network of this sort both critical. The desired phase shift is obtained by phase and amplitude deviate somewhat from the tuning this circuit, and when it is at resonance, ideal condition. However, the phase should hold t,he phase shift will be approximately correct. within a few degrees and the amplitude within a However, at resonance the rate-of-change of few per cent. phase with tuning is greatest, and is proportional While set up for this test, it is interesting to tv the circuit Q: hence it is desirable to make the feed a voice signal into the network and observe tuning less critical and the phase setting easier the result. A complex voice wave produces a by reducing the secondary Q. remarkable pattern of curlicues and circles within circles - a pure "pear-shaped" tone, of course, Testing & Adjustment always produces a circle no matter what the Testing and tuning up the circuit is quite frequency, provided it is within the range of the straightforward. The first step is to see that the network. It is possible that patterns of this sort correct oscillator voltages are applied to t,he might be useful for voice training, or in connec 6L7s. (A 20,000-ohm-per-volt voltmeter plus a t.ion with teaching the deaf to speak. crystal rectifier makes a convenient substitute With the detectors balanced, the networks con for a vacuum-tube voltmeter, as suggested by nected, and the oscillator at the correct, frequency, W0TQK.)~ The injector grids may have up to the radio-frequency phase shift must be set. 15 volts r.m.s. applied, in accordance with con Tuning the i.f.-transformer secondary to reso ventional converter practice. It is desirable that nance will give approximately the correct setting. all four tubes receive roughly the same oscillator An easy way to find the correct setting exactly is voltage. Maximum voltage at the signal grids to connect the horizontal and vertical plates of a should be held to one or two volts r.m.s. The 'scope to the outputs of the two balanced de balanced detectors are balanced by applying a tectors. With a c. w. signal applied to the input and 4 A. H. Nichols, "A Single-Sideband Transmitter for adjusted to a frequency that produces, say, a Amateur Operation." QST, January, 1948. 1000-cycle beat note, the tuning is adjusted until _· .. !??\/" .{'-1'•-- • Ii cct Bottom view of the halanced detector_ chassis. • QST for INCOMING FREQUENCY HIGHER THAN THAT OF OSCILLATOR other closes, and one control would thereby be eliminated.. The single-sideband detector is then ready to Audio ~ er! ouitiut, f,rst go. Its output may be fed back to the audio input t ba/'a.,,ad detecwr (A) Relative f'_ha,se:, outputs of the receiver, or it may be fed to a separate of first w- • Underneath the phase-shift net work chassis. The two networks side by side are electrically the same, al though the components are not al ways identical. • June 1948 The shape of this curve is to a large extent dependent on the exact frequency chosen for perfect balance - in this case somewhere be tween 650 and 900 cycles. In operation, this amount of rejection is rea sonably adequate. (Selection of condensers and resistors of closer tolerance would probably have meant still better performance.) It is very striking to be able to throw the sideband selector switch, when listening in a crowded c.w. band, and hear an entirely different set of signals! An attachment of this sort effectively halves the bandwidth of the c.w. receiver, thereby removing half of the signals one would normally hear. 6 A remarkable Close-up of the plug-in adapter unit for connecting to feature is that this great increase in selectivity is the receiver. obtained without resort to crystal filters or other highly-selective circuits which require great sideband signals, that the selector switch must be stability or careful tuning for proper operation. thrown to the correct position. If it is on the Another remarkable feature is the fact that two position which rejects the sideband being trans audio outputs can be provided, so that two mitted, the station will be heard very poorly. operators can listen simultaneously and without In certain types of s.s.s.c. transmitters, it is interference to the output of the same receiver - possible to select the sideband transmitted at will. When, at the receiving end of a circuit, the receiver is equipped with a sideband selector, it is possible to change frequency instantaneously \ from one sideband to the other merely by throw '· 1 ing a switch. Thus a QSY of one channel-width can be accomplished without any retuning. In ham work, this should be ideal for avoiding QRl\f. ,o~·-- 1 '\ NC-200/.F. \ ..-:.---SELECTIVITY ;&:Str0;y~ Numerous BCLs in Kendallville, Ind., com plained loudly about.:'..the radio ham who was making it impossible for them to hear any pro grams. They carried their demands that some thing be done to t.he local politicos. It was, too. Intensive investigation disclosed that the cause of all the listeners' woe was centered right in City Hall --- not high-powered oratory, mind you, I "" 500 but a high-tension line carrying 2300 volts which was arcing over at intervals I - f ndianapolill 1000 Star, via W9RDW lOW-PASS FILTER I> RESPONSE ~-~ 1' 1-++-+--,-,---,----.---t---t--t----1"-c-·· - , We're in, gang! The new ,lmerican College ...... ,.. Dictionary (Random House), distributed by the I I Book of the Month Club, gives listing to the 5000 a s ..,. s Ei 1 e 9 10 11 J2 u 1-4- 1s f6 expression "ham radio," defining it as slang for AUDIO FREQUENCY IN Klt.OCYa.£S "an amateur; a radio ham." - WJBT Pig. 7 - Response curve of the low-pass filter (solid curve). A typical receiver selectivity .curve is shown for comparison (broken curve). Nonmetallic permanent magnets, known as "Electrets," are now being made of plastics, one hearing all signals lower than the beat oscil usually by solidifying a molten wax in a strong lator, and the other all those higher. It is only d.c. electric field. - - Ohmite News necessary to add a second 6SL7 connected to the unused terminals of the 90-degree networks in "Amateurs modifying surplus-gear and)ooking Figs. 3 or 5. This ought to be an ideal arrangement for a solvent for Glyptal will find a friendly ally for more-than-one-operator stations in DX or in ethylhexanedoil, commonly sold as the insect SS contests; each operator can listen for replies to repellent '612.' Twelve hours after the solution CQs on his particular side of the transmitter i'l applied, the Glyptal will brush off.'' -- C. Ji'. frequency! A[a.c.Lean It must be remembered, when tuning in single- Swell tip, Mac; we'll try it. But please tell us, ti The authors refer here to a "straight" super -~ 0 one OM: Do you think the stuff also might help in without a crystal filter. - Ed. debugging that pestiferous 807 of ours·( 18 QST for Amplifier Instability in Transmitters Its Investigation and Treatment BY DONALD H. MIX,* WlTS for the specific references to the screen, the re • Although quite a bit has already been marks and circuits which follow apply to triodes published about how to build and adjust 11,s well as beam tetrodes. Under the measures to amplifiers in transmitters, it is apparent be prescribed, it has been possible to operate a that what has been said hasn't bc,,n en pair of 807s in push-pull at zero bias, without tirely adequate, for many still have load, running at an input up to the rated plate trouble confining the output to one fre dissipation level, with no sign of instability of any quency at a time. This article reviews some of the measures for stabilizing kind. Most users of 807s will agree that this is triodes and tetrodes suggested in the not a usual experience. past, finds that some of, them can be improved upon, and ends up with an ar Checking Procedure rangement that gives a reasonable guar Transmitter amplifiers are subject to one or antee of complete freedom from am more of three common modes of oscillation, all plifier oscillation in any form, without of which appear to be of the t.g.t.p. variety. relying on loading as the stabilizer. It There may be others but they are not often en should he of particular interest to those having trouble with 807s. countered. In addition to oscillation at the operating frequency (the frequency to which the amplifier is tuned by the conventional input and UCH has been written on the subject of output tank circuits), parasitic oscillation at stabilizing r.f. amplifiers in transmitters. frequencies in the vicinity of 150 Mc. will almost M And yet many of us are still having plenty invariably take place in both triode and tetrode of t,rouble with the various types of instability to amplifiers unless steps are taken to suppress it. which modern tubes with their high power The plate-grid capacitance of tetrodes designed sensitivities seem to be prone. Still others are for transmitter use is seldom sufficient to support operating unconscious of the probability that t.g. t.p. oscillation at low frequencies. But parasitic much of the widespread clicking and splattering oscillations at frequencies as low as 100 kc. have within the bands, as well as spurious signals been experienced wi.th triodes and poorly-screened frequently found outside, may originate' in an audio tetrodes, such as the 6L6 and 6V6, when unstable amplifier which appears on the surface suitable eircuits have been permitted to exist. t,o be quite innocent of such transgressions. No Fi/I,. 1 _,_ Diagram of indi amount of click filtering will remedy this sort of catitlg absorption wavemetcr t,rouble, of course. The fact that an amplifier for checking amplifier instabil doesn't oscillate when fully loaded and biased to ity. L1C1, with plug-in coils. should cover a range from 200 cut-off is no guarantee that it may not take off Mc. to 200 kc. L2 is a pick-up intermittently with keying or modulation, or coil of several turns coupled to when detuned from some fortunate adjustment,. l,1. The crystal is a Type l N34. C2 by-passes the meter (1-ma. Neither is a clean signal at the operating fre scale). The portion of the circuit quency proof that parasitic oscillation at some to the right of La is used as a other frequency is not taking place simultane neutralizing indicator. ously. The power sensitivity of beam tetrodes in particular is so great that oscillation of one type Troubles of this sort often are difficult to diag or another can hardly be avoided unless more nose under normal conditions of bias and load. t,han-ordinary precautions are taken. The best step toward assurance that transient For the sake of completeness, some of the fol oscillation won't take place during normal lowing will eonstitute repetition of t.hings that operation is to adjust voltages and reduce loading have been said before. In the light of more ex so that couditions are favorable for sustained tended experience, some principles which have oscillation, when obRervation is easier, ,and then been more or less generally accepted will have to devise means for suppressing it. This can be done be questioned. It is believed, however, that it is by using grid-leak bias with no fixed bias and now possible to point toward a procedure which operating the amplifier without load, reducing seems to give reasonable assurance of real sta screen and plate volt.ages as necessary to limit the bility without the need for complications in con input to the rated dissipation level. Each stage struction or difficulties in adjustment. Except in the transmitter should be tested separately. * Assistant Technical Editor, QST. The only tool required, in addition to the usual June 1948 19 ---- grid and plate milliammeters, is an indicating the ca,se of capacitance coupling) and the 80- absorption wavemeter of the type described in meter plate tank coil should be plugged in. This the last several editions of The Radio Amateur's is to make sure that the amplifier can't oscillate Handbook. The diagram is shown in Fig. 1. In at other frequencies by means of the regular tank cidentally, this little gadget is something no ham eircuits. The tank coils should not be short should be without. It has many important uses circuited as an alternative, because the amplifier around a transmitter. may oscillate at a frequency determined by the inductance of the shorting leads! A jumper should V.H.F. Parasitics be placed across the plate r.f. choke if one is used. Parasitics in the v.h.f. range perhaps are the Thus whatever oscillation takes place will be easiest to segregate. Apparently the oscillatory confined pretty well to the v.h.f. parasitic we're circuit is composed principally of the leads from looking for. If the stage is an intermediate one, the grid and plate to their respective tanks, series the tubes in the preceding and following stages tuned by the tank condensers, as indicated by should be removed to eliminate loading. If a the heavy lines in Fig. 2-A. The same sort of cir Variac isn't available, a lamp socket ean be con cuit exists if the tank is balanced. It is chiefly nected in series with the plate-transformer with this circuit in mind that the importance of primary and lamps of various sizes tried until one short leads often is stressed, the theory being is found that will limit the power input to the that if the leads can be made short enough, the amplifier to just under the dissipation rating. resonant frequency will be so high that the circuit Screen voltage, in the case of a tetrode, should be losses will prevent oscillation. Unfortunately obtained from the plate supply through a drop this objective seems hardly possible of attain ping resistor of recommended value. ment, since even if the lead le,ngth could be With power applied to the amplifier only, a reduced to zero, there remains the inductance of careful search should be made by adjusting the the tank condenser and the leads within the tube. 1:,>rid tank condenser to several settings, especially Before turning on the amplifier power, the 10- including minimum 8,lld maximum, and turning meter grid coil (the plate tank coil of the driver in t,he plate tank condenser through its range for each of the grid-condenser settings. Any grid current reading or any dip or slight flicker in plate current indicates oscillation. This can be confirmed by using the absorption wavemeter held close to the plate lead of the tube. As the wavemeter will indicate, when tuned to obtain a deflection, the parasitic usually falls somewhere in the vicinity of 150 Mc., regardless of whether the tube is a triode or a tetrode. The oscillation may take place only at a certain combination of t,ank-condenser settings, but it may happen to be just the one most used in normal operation of the -I amplifier. The most common way of suppressing v.h.f. parru.-itics with tetrodes has been to use a small choke in the grid lead in conjunction with a small unby-passed noninductive resistor at the screen, as shown in Fig. 2-B, RFC1 and R1. While this combination seldom fails td suppress the parasitic, it has been found that even a small amount of resistance - as low as 10 or 12 ohms - used in this manner has a very serious effect upon the plate-grid isolation at the operating frequency. In searching for an alternative method of sup pressing a v.h.f. parasitic with 807s, tuned traps were tried at the grid, at the plate and in both positions simultaneously. While this was effective (C) over a portion of the tank-condenser range, the Fig. 2 ---- A - V.h.f. parasitic circuit hidden in high condenser changed the frequency of the parasitic frequency amplifier. B - Common method of suppress enough so that one adjustment of the trap would ing v.h.f. parasitic with tetrodes. Ri, however, is not recommended. C ·- Recommended circuit for beam not hold over the entire range. On the <-.ltance tubes. Chokes in both plate and grid suppress v.h.f. that a long plate lead might result in a parasitic parasitics without the disadvantages of B. Suggested plat€ circuit tuned to a frequency lower than dimensions for RFC1 are 15 turns No. 22 wire, ¼-inch diameter, close-wound; for RFC2, 8 turns No. 14 wire, that of the grid where the t.g.t.p. circuit, if it :\4 inch long, self-supporting (see text). was such, could not oscillate, the plate lead was 20 QST for lengthened. This proved to be a complete remedy, Fig. 3-A shows a conventional arrangement although the grid choke is necessary also, for a with parallel feed throughout. For low frequencies reason that isn't quite apparent. Accordingly, the the tank coil~, Li and L2, have negligible reactance plate lead, which was about a foot long, was and may be considered simply as long leads short wound into a coil and inserted close to the plate, circuiting the tank condensers, C1 and C2. The as shown in Fig. 2-C, RFC2: circuit for low frequencies then becomes that In several 807 amplifiers built within the last shown in Fig. 3-B. Even if the by-pass condensers, couple of years - single tube, tubes in parallel or CG and Cs, are small, or omitted entirely, the push-pull-a grid parasitic choke of about 15 turns of No. 22 wire close wound on a ¼-inch form has always worked. It seems to be critical only to within a turn or two. With this as a starting point, the plate lead should be lengthened until oscilla tion ceases, making sure that the long plate lead is kept well away +B -c +SA +B -c from the input circuit. When the (A) minimum length has been found, the wire can be wound on a small- diameter form and inserted in the plate lead close to the tube terminal. The ones we have used with success in a push-pull 807 amplifier consist of 8 turns of No. 14 wire, ¾6-inch inside diameter, %: inch long, self- . supporting. Since there has been insufficient time for extended ex perience with this arrangement in -c +S.G. -c other amplifiers, it is possible that (B) these dimensions may need changing in another layout. Fig. ,1 ...... A - Conventional capacitance-coupled amplifier with A grid choke of the dimensions parallel feed throughout. B - Possible low-frequency parasitic circuit in heavy lines. Values in this circuit seldom are appropriate for oscilla given above usually suffices to tion. however. r1uench v.h.f. parasitics in triode amplifiers. In stubborn cases, a tuned trap circuit still will be completed through power coru;isting of 4 turns of No. 14 wire, % inch in supply filter condensers or a biasing battery, both diameter, ~i inch long, tuned by .a 30-µµId. mica of which have negligible reactance to low fre t,rimmer inserted in the plate lead, may be re quencies. The tanks then are composed essentially quired. No grid choke is used. of the grid choke, RPC2, tuned by the coupling condenser, C5, and the plate choke, RFC,, tuned Low-Frequency Parasitics by the blocking condenser, G'9. It will be noted So much for v.h.f. parasitics. Attention can that neither the plate choke of the preceding stage now be turned to any low-frequency parasitic nor the grid choke of the following stage comes which may exist. As stated previously, a parasitic into the picture, because the only connection is of this mode seldom is experienced with well the common ground or chassis connection. screened tubes. But it is just as easy to arrange In practice, the coupling condenser seldom ex the circuit so that it can't happen anyway. Oscil ceeds 100 µµfd., while a 2.5-mh. r.f choke is used lations of this ,type may take place in amplifiers universally for RFC2. This gives an LC product where r.f. chokes are used in both plate and grid of 250. In tlie plate circuit, a blocking condenser circuits when coupling and blocking condensers of 1000 µµfd. (0.001 µfd.) is most often used and or, more often, the tank condensers themselves the plate choke is seldom less than 1 mh. in combine with the chokes to form tuned circuits transmitters working no higher than 30 Mc. of low frequency. The belief that a sequence of These values give an LC product of 1000. Thus, r.f. chokes in a succession of parallel-fed circuits it is obvious that t.g.t.p. oscillation should not in itself necessarily leads to low-frequency take place with ordinary values. parasitics is not uncommon. However, t.g.t.p. The situation changes considerably, however, oscillation requires that the plate circuit be tuned when a eonventional balanced circuit is used in to a frequency higher than that of the grid circuit either grid or plate with r.f. chokes in both. Fig. and this condition seldom prevails with values 4-A shows such a circuit with balanced output. used in practice, so far as single-ended circuits are Fig. 4-B shows the low-frequency circuit that lurks concerned. beneath the surface. This time, the tank coil, L?_, June 1948 21 serves not to short-circuit the tank condenser center-tap would cause a greakr voltage drop but, considerably worse, to connect the two than could be afforded. However, this did not sections in parallel across the plate r.f. choke. prove to be the case when it was tried. As little The difficulties are the same with either a single as 100 ohms could be used. This is fortunate be tube or two in push-pull. cause the low resistance substituted for RFG2 in The grid-circuit LC product, we have seen, is Fig. 4-B effectively shunts the grid choke of a about 250 with usual values. The plate tank con following stage, which in this case can serve a.q denser seldom will exceed 100 J,<µfd. per section, the inductance tuned by 02. or a total of 200 µµfd. maximum across RJ/C2 In link-coupled push-pull circuits, the grid which usuallv is 1 mh. Thus we see that even with choke, which is tuned by the sections of the grid the tank con:denser at maximum capacitance, the tank condenser in parallel in the parasitic circuit, LC product cannot exceed 200. A 2.5-mh. plate can be eliminated by the substitution of the grid choke will bring the figure up to 500 but. only at leak resistor, as shown in Fig. 5-A. With capaci maximum capacitance of the tank condenser. At tance input coupling as shown in Fig. 5-B, how all settings below half capacitance, the plate cir ever, the plate choke of a parallel-fed driver can cuit will be tuned to a frequency higher than that serve as the parasitic grid inductance. The low of the grid circuit. In fact, the plate choke can be frequency circuit is shown in Fig. 5-C. Thus it is increased to almost any size within practical seen that R1 must be of low value if oscillation is limits without improving the situation materially, to be prevented. This can be accomplished by because the plate circuit always can be tuned to a making R1 100 ohms or so, by-passing the lower frequency higher than that of the grid when the end to ground, and then adding grid-leak re sistance or any other biasing system desired, as shown in Fig. 5-D. This permits the use of the series choke in the plate circuit or parallel plate feed if desired. In searching for low-frequency parasitics, the tubes in the prececling and following stages should be removed as before. The wavemet-er should be held close to the grid or plate r.f. choke. Operating-Frequency Oscillation with +B -c +SG. +II Tetrodes (A) When the statement is made by the manu facturer that a bE'.am tetrode docs not require neutralization, tight shielding and the fact that a screen-grid tube should never be operated without load to prevent damage to the screen doubtless arc ta.ken for granted as a consideration. But there is some doubt as to whether or not it is safe to rely too heavily on normal loading as a de pendable means of stabilization. A condit,ion is -c +S.G. B+ frequently encountered in practice when an 807 (B) will appear perfectly stable when running loaded Fig. 4 - A - Conventional capacitance-coupled am with uniutcrrupkd excitation and without modu plifier with balanced output circuit and parallel grid lation and yet will develop widespread clicks feed. B - Resulting low-frequency parasitic r,ircuit in heavy lines. when the transmitter is keyed, or splatter when the amplifier is modulated. \Ve have seen more tuning condenser is set at or near minimum. than one commercial installation with heavy The most obvious remedy is to eliminate at loading resistors across the tanks and they least one of the chokes. However, the grid choke weren't put there to increase tank-circuit cannot be replaced by a resistor without involving efficiencv ! considerable loss in excitation. The plate circuit A check with an r.f. indicator will show that is series fed but the choke is necessary to break up there is plenty of driver r.f. getting through to any harmful resonances which may be set up in the plate tank circuit in any unneutralized 807 the individual t,auks t.hat are formed when the amplifier. Neutralizing shows that most of it is coil center-tap as well as the condenser rot.or are coming through the grid-plate capacitance, be it grounded. A check also showed that the second internal or external. Even though a tetrode may harmonic output increased with this connect.ion. never be operated without load, it is pretty safe 'The condition was even worse with the 'condenser to say that if it is made stable without load, there rotor floating. In considering the substitution of will be little chance for trouble when load is a resistor for the plate choke, it had been assumed applied. It isn't difficult to arrive at an arrange that any value sufficiently high to isolate the ment of components which will permit the intro- 22 QST foi ,luction of i:;imple homemade spaced-disk type eliminated as previously described, l,y removing neutralizing condensers. The ones we have used t,he screen suppressor resistors. After reneutraliz with 807s consist of a long flat-head machine ing, the amplifier became perfectly stable on all screw with its head working against a stationary hands without load. There still remained some :hi-inch disk. The leads 'to the condenser should slight indication of energy in the plate circuit at be kept short, of course, so that they will not 20 and 10, but the feed-back was irnmfficient to couple into other parts of the circuit. support oscillation. It was found that the ampli The indicator part of the absorption wavemeter, fier required different neutralizing adjustments that is, the crystal and by-passed milliammeter for t,he extremes of 80 and 10. This condition was in series, makes a very sensitive neutralizing improved considerably by returning the neutral indicator. When building one of these wave izing condensers to the tank side of the grid meters, it is a good idea to bring out terminals so that this portion of the instrument can be used separately. These terminals are simply connected to a link coupled to the output tank coil. Neither grid-current fluctuation nor a neon bulb is a satis factory indicator for neutralizing tetrodes. With the exciter running, but with the ampli fier plate and screen voltages off, the neutralizing indicator normally will show considerable energy in the plate tank circuit when it is tuned to resonance. The neutralizing condenser should be adjusted to the point where the indicator reading dips to its lowest point. It should be possible to find a minimum with a rise on either side some where within the neutralizing-condenser range. The neutralizing condenser should be adjusted witli. a long rod of polystyrene, wood or bakelite, sharpened to a screwdriver edge at one end, so t,hat hand capacitance will not complicate the adjustment. If the amplifier is push-pull, the two neutralizing condensers should be kept at equal settings. Adjustment of the neutralizing con denser will have some effect upon resonance, so the tank condenser should be readjusted for reso Mnce after all but minor changes in neutralizing capacitance. The output circuit of single-tube am plifiers should be carefully bal anced by connecting .a condenser across the neutralizing-condenser end of the tank circuit to com pensate for the tube output ca pacitance ac,ross the other end, +e +S.$. +e as shown in Fig. 6, C1. (C) Before neutralizing, a pair of 807s with which we were working would oscillate at the operating frequency on all bands unless some load was coupled to the amplifier. The load required to stabilize t,he amplifier at the higher frequencies was considerable --in spite of the fact t,hat there was plenty of shielding between the in Fig. 5 ·-·-A--' Conventional link put and output circuits. With neutralizing, all coupled push-pull trace of feed-through of driver energy to the plate amplifier eircuit circuit disappeared at 80 meters, and the am• with grid leak, R1, replacing cw,tom .. plifier was perfectly stable with all load discon +B ary ,grid c!10ke. B nected. However, although the amplifier did not -- Capac1tance oscillate at 40, the indicator showed some energy coupled push-pull input circuit with series grid feed and getting through to the plate circuit. It became parallel driver plate feed. C ...... Low-frequency parasitic drcuit resulting from arrangement of B. D - R,, whose so gi:eat at 20 and 10 that the amplifier oscillated value is low, serves Loth to isolate the coil center-tap readily on these two bands unless heavily loaded, and load the low-frequency parasitic circuit. R2 is the and could not be neutralized out. This was fiMily usual grid leak. C1 should be not less than 0.01 µfd. June 1948 23 parasitic chokes as shown in Fig. 6, instead of tance-coupled push-pull amplifier with which we directly to the grid terminals. No further im were working, provision for balance, as shown provement was found by tapping along the grid at 01 in Fig. 7, was included. The output capaci leads within the latitude permitted by the con tance of the driver tube was looked up in the struction. When the amplifier was neutralized on tube data and the balancing condenser, l\, was lO, the adjustment held satisfactorily for the set to what was estimated roughly by eye to be lower frequencies. an equivalent capacitance. The amplifier per To some, the introduction of neutralization formed very poorly. '£he output was consider may be considered a complication which shouldn't ably below the rated value and the dip in plate be necessary with screen-grid tubes. However, a current at resonance was negligible when the amplifier was loaded to rated input. Finally, it was noticed that one plate was showing some coloring. A check of the individual screen cur rE>,nts (a convenient indication of balance in a push-pull amplifier, since the tank circuits don't have to be opened up for the meter) showed that one tube was drawing almost no screen current, while the screen current of the other was consid erably in excess of its rating. It was found that a very careful adjustment was necessary to bring -c +S.G, +B the two screen currents to the same value. The Vig. (i - ln neutralizing single-tube amplifiers, a difference in performance after accurate balancing balancing condenser, C1, equal to the tube output capaci was remarkable. Good efficiency was obtained tance, should be used. and off-resonance plate current increased to between 850 and 400 ma., giving a very pro push-pull stage, or one with balanced output, nounced dip to the rated 200 ma. at full rated requires the addition of only the neutralizing load - and this with the screens supplied from condensers. A compensating fact is that tight a dropping resistor. Apparently, before balancing, shielding becomes unnecessary. In this particular one tube had been doing almost all of the work. instance, the feed-through of driver energy to With one tube loaded up to nearly 200 ma. it the plate circuit actually decreased when shield isn't surprising that the plate-current dip was ing surrounding the lower portions of the push negligible! pull tubes was removed. It was found that Let us repeat, too, another reminder. Hold the removing the shield from the grid coil, which grid current of 807s and other beam tubes to was at right angles to the plate tank coil but not the rated value at the recommended operating far from it, added nothing noticeable to the small bias. Overdriving spoils the performance of tet amount of energy fed through after neutraliza rodes by running the screen current up unneces- tion was completed. Quite a bit has been said, from time to time, about the importance of avoiding long or com mon return paths for by-pass condensers in relation to stability. Such a thing is difficult to confirm in practice, especially when the am plifier is already stabilized. But we did move the grounding points for the screen by-passes around on the chassis within the radius of the condenser leads with no detectable change in operation. 8+ -c +S.G Using a lO-inch clip lead, the plate by-pass was grounded at points spread all over the chassis, Vig. 7 - The excitation to push-pull tubes can be balanced by use of a balancing condenser, C1, in the top and bottom, with equally unimpressive re input circuit. Its value should he the same aa the output sults at a highest frequency of :30 Mc. Short capacitance of the driver tube. returns discourage harmonics, however. sarily. With a series resistor, this drives the screen Balancing Push-Pu.II Drive voltage down, making it difficult to load the Before concluding, .perhaps it is well worth amplifier properly. while reminding those who build push-pull ampli Summary fiers of the importance of balancing the drive to The important points of the foregoing can be the two tubes. This becomes even more impor summarized by the following list of dos and tant when using tubes like 807s, since underdriv don'ts: ing of one tube can combine with the harmful 1) Suppress v.h.f. parasitics with v.h.f. chokes effects of overdriving the other to give some in the grid and plate, following the dimensions pretty discouraging performance. In the capaci- (Continued on paoe 110) 24 OST for A Coaxial-Line Receiver for 220 and 235 Mc. Making the Most of the Superregen on 1¼ Meters BY C. VERNON CHAMBERS,* WlJEQ also prevents most of the radiation which would occur if the detector were coupled directly to the • Tube for tube and dollar for dollar it's r.f. still p1:etty hard to beat the old supetre antenna. The circuits of the receiver can be gen for v.h.f. applications. He1:e, through made to cover both the 220- and 235-Mc. bands, the use of a simple tuned r.f. stage and a or it can be made to tune either one of the bands coaxial-line detectol' circuit, the weak with a considerable increase in bandspread. nesses of the superregenerative receiver Otherwise, the receiver is of the old rush-box are largely corrected .. Sensitivity and variety. It still is the type of receiver that c,;i,n s..Jectivity are improved, and annoying be thrown together with the least amount of work detector radiation is held to a minimum. and expense and, after the screwdriver and hack saw have been put away, it doesn't take an E.E. to make it behave properly. ESTS made in the ARRL lab on the coaxial line receiver recently described in QST by Circuit Details TWlNXY 1 indicated performance so much The circuit diagram of the receiver is shown in better than other superregens on 144 Mc. that Fig. 1. The plate circuit of the r.f. amplifier em the possibilities of a similar technique for 220 and ploys a self-resonant loop, L3, which is tuned to 235 Mc. were investigated. Though the con the middle of the operating range by the tube ventional superregenerative circuits used for and-circuit capacitance. A slight increase in re years on lower frequencies can be made to work ceiver sensitivity can be obtained by tuning the on 235 or 220 Mc. with almost equal performance, plate circuit, but the small improvement does not their inherent weakness, broad tuning and severe appear to warrant the extra complications in radiation, make them of dubious value for use on volved. any band where there is appreciable activity. The detector is a 6AK5, with the concentric ,Just as was the case with the 144-Mc. job built line connected in its grid circuit. In most respects by WlNXY, the !¼-meter receiver built in the it is similar to that of the WlNXY receiver, and ARRL Lab shows improved selectivity, smoother the points made by Santangelo apply equally to performance, and lower radiation than are possi this model, except that somewhat higher screen ble with the simpler types. The detector circuit is voltage may be needed for superregeneration at similar to the WlNXY receiver, except for the the higher frequency. modifications required for the higher frequency. The audio output of the detector, which is fed The r.f. stage differs, in that a 954 triode is used. through a quench filter consisting of Cg, C10, Cu This stage not only provides appreciable gain but, and RP'Ci, is low, with the coupling arrangement by reducing the effects of antenna resonance, it shown, and this could be corrected (if a single makes the tuning of the receiver and the setting audio stage is desired) by connecting the primary of the regeneration control much less critical. It and secondary windings of the audio transformer * Technical Assistant, QST. in series, and using it as an audio ehoke. The 1 Santangelo, "Coaxial-Line V.H.F. Rereivers, "( QST, March, 1948. • Front view of the coaxial-line receiver. The r.f.. amplifier tuning control is at the left and the main con trol, for the concentric-line detector circuit, is at the right aide of the unit. The audio gain control, •end-receive switch, 'phone jack, and regeneration control can be seen in that order, from left to right, across the front wall of the chassi•. ' • June 1948 Rrc, IIE 954 6.AK5 6J5 6V6 ls {\f ·0f+' Cz,* I - S.3\(- 250V~+ [?ip,. l i~ Circuit diagram of the supcrregencrative receiver. C1 - Midget variable condenser (Millen 21)015 reduced Rn - 2200 ohms, !1:1 watt. to one 8tator and two rotor plates). R12 -- 0.1 megohm, h watt. C, - Midget variable condenser (Millen 20015 reduced R,a-OA7megohm, ½ 1 26 QST for The L-shaped bracket for the r.f. amplifier is power wiring may be passed down through the 2.!f inches high, has a depth of 2¾ inches, and is main chassis. l !i inches across the front. Spade lugs are Construction·of the concentric line is not diffi bolted, and then soldered, to the bottom of the cult if the various operations are carried out as partition to provide a method of mounting that is suggested below. The inner and outer conductors both electrically and mechanically sound. The are 4 inches long, and the end plate is 2),f inches National XLA tube socket is centered on the side square. A Hi-inch hole for the inner conductor of of the partition at a point located 1 % inches in the line should be drilled at the center of the end from the rear and top edges. A ~,:l'. 6-inch hole, plate, and the plate should also have a hole for a drilled in the bracket at this point, allows the %2 machine screw at eaeh corner. However, grid prong of the !J54 to extend through to the before the center hole is drilled, it is advisable to grid-circuit components. The cathode and heater use the center-punch mark as the pivot for prongs of the socket face toward the front of the scribing a circle to indicate the position of the receiver and the XLA-C by-pass condensers are ou1;side conductor. This will simplify the task of mounted inside the socket. The plate by-pass lining up the two pipes for the soldering operation. condenser, C'6, is mounted underneath socket A %-inch hole should now be drilled in the large prong No. 5 as this prong is used as the support pipe at a point located 1 inch up from the bottom point for the cold end of the plate loop, L3. Note edge, and a second hole of ;½'. 6-inch diameter that the No. & prong is a spare as far as the 954 should be drilled on line with the larger hole and is concerned. A National XLA-S internal shield, around the pipe by 90 degrees. After the material designed for use with the XLA socket, provides between these two holes and the bottom of the a common path for the condenser ground con tubing is removed by cutting with a hack saw, nections and, of course, this soldering should be the finished slo1;s will provide openings for the done before the socket is bolted to the copper input coupling coil, La, and the detector-grid partition. The heater, cathode, and suppressor connection. The inner conductor should also be connections are also made to the internal shield drilled and tapped for a % 2 machine screw at this and, after mounting, the shield is in turn soldered time. One hole, 3,1; inch up from t,he bottom of t,o t,he copper plate. the line, is required if the receiver is to be used to The r.f.-amplifier tuning condenser is mounted cover only one band. A second hole, Ji inch with the shaft in line with the shaft of C2. Stator above the first, is necessary if the receiver is to be terminals face to the left so that the bottom tuned to both the 220- and 235-Mc. bands. In terminal is within a 74 inch of the 954 grid prong. either case, the tapped hole will be used as t.he L2 is supported by 1;he condenser terminals and eonnecl,ing point for the lead running to the tun the antenna coil, L1, is supported by Li and by the ing condenser, C2. two-terminal lug strip located to the right Of the Unless extremely thin-walled tubing is used for amplifier. Grid clips for the 954 were improvised the concentric line, it will be difficult to complete by removing the prongs from a miniature tube the soldering operation with an ordinary iron. socket. Placing the assembly on an electric hot plate will Holes, large enough to dear %2 machine heat the copper in a very few minutes and will screws, are drilled at each corner of the copper allow the work to be done neatly and easily. The mounting plate so that the unit may be mounted end plate should be laid on a flat level surface on l½-inch stand-off insulators. Larger holes, while the inner conduct.or is lined up perpendicu equipped with rubber grommets, are adjacent to lar to the horizontal surface of the plate. This the detector and amplifier tube sockets so that operation may be carried out with the metal • .Rear view of the superrcgenerative receiver. The r.f. circuits are mounted on a copper shelf to the left of the antenna terminals. The detector tuning condensor is mounted on a small panel to the front of the coaxial line, and the band-set condenser is soldered across the open end of the line. The r.f. stage is mounted on an L-shaped bracket with the tube socket and plate-circuit "compo nents on the left side and the grid circuit on the right side. Audio tubes and voltage regulator are in line acrosa the rear of the chassis. • June 1948 • Bottom view of the coaxial-line receiver showing the output transformer, T2, located at the lower left-band corner of the chassis, and the audio transformer, T1, mounted between the sockets for the audio tubes. The <1uench-filter choke, housed in a metal shield, is above and to the right of T1. Resistors R1 and Rt, are mounted on Clld to the right of the regulator-tube sockt"t. • is at the high or the low end of the band. Of course, if the set is being lined up for two-band operation, it is necessary to set the tuning con densers well toward minimum or maximum resting on the hot plate if the latter is to be used. capacitance depending on which of the two bands The outer conductor should be placed in the is being tackled first. position indicated by the scribed circle. Heat The bandspread of the detector circuit can be may now be applied and the soldering com adjusted to allow a full band to occupy approxi pleted. The metal is ready to accept solder when mately 60 divisions of the main dial, this being a rapid change in the color of the copper is obtained with the 6AK5 grid tapped up ¾ inch noticed. A long piece of solder may be inserted from the grounded end of the line. If it is neces through the open end of the line, and as the end sary to change the tap to alter bandspread, it is is moved around the surfaces to be joined the advisable to readjust the band-set condenser, solder will melt and run into place easily. and to realign the r.f. stage. The remaining constructional work is straight The setting of the regeneration control, after forward and study of the three photographs will alignment of the receiver, is important, and it show the location of the various components. should be adjusted to permit maximum receiver Since there is no crowding of parts, it should not sensitivity. It will not require readjustment be difficult to duplicate the original layout. over the band, except perhaps to accommodate different types of signals. Testing The input circuit of the receiver is intended for Operation of the receiver is similar to t,hat of operation with a 300-ohm line. However, it can lower-frequency types and the tuned circuits be used with a low-impedance line, and if single should be lined up by means of a signal generator wire feed or coaxial line is employed,, one end of or by listening to amateur signals of known fre the coupling coil, Li, should be grounded. quency. A power supply capable of delivering 250 volts at 40 or 50 ma., and 6.3 volts a.c. at 1 '.&-Stray~ ampere, should be used. It will be especially helpful if the test signal can be set at the center Having trouble getting your underground of the band, or bands as the case may be. The antenna to perk? Don't fume and exhume, OM I first indication of proper operation will be the Instead, take W5NIY's suggestion and string a usual superregenerative hiss heard after power half-wave counterpoise 30 to 40 feet in the air. has been applied and the superregeneration con Bernie guarantees that this will end your troubles. trol advanced in a clockwise direction. The tun ing controls, C1 and C2, should now be adjusted QST is interested in keeping a running file on so that their plates are half-meshed, and the input the users of single-sideband suppressed-carrier signal should be coupled to the receiver. Ca, the transmission who are springing up all over the band-set condenser, is now adjusted for maximum country. Anyone who has not done so is cordially receiver response to the test signal. The grid coil invited to write and tell us of his activity. Please of the r.f. amplifier may be slightly off resonance address yotµ' correspondence to ARRL, West at the beginning of the test and this is corrected Hartford, Conn., attention of Assistant Technical by increasing or decreasing the length of the Editor Byron Goodman, WlDX. winding. The procedure outlined above is also used when the test signal is located near the edge of the SWITCH band. However, the tuning condensers are first adjusted to either maximum or minimum capac TO SAFETY! itance, depending upon whether the test signal 28 OST for the Month BOARD HIGHLIGHTS again rejected. Special elections were ordered Ju a packed two-day-and-night :;e;;sion with held when there is a vacancy in the office of every director present, t.he ARRL Board of alternate director. The Canal Zone was incorpo Directors at its annual meeting in early May rated in the Southeastern Division. decided to ask F'CC to expand the 75-meter The position_of tha amateur institution in re 'phone allocation toBS00--4000 kc. The question spect of its frequencies and its relations with the of 7-Mc. 'phone was carefully examined but over Government and the public was carefully exam whelmingly defeated. t:lcntiment. was divided on ined. Plans were made for participation and expanding 14-Mc. 'phone but after a long and representation at the coming Inter-American con detailed discussion it was decided that our best ference at Bogota, where regional frequencies will interests were served by leaving the band as it is. be allocated to services, Secretarv Warner and The Commission is requested to make n.f.m. Assistant Secretary Budlong we;e commended 'phone permanent in the lowest 50 kc. of the for their achievements on behalf of amateur radio 75- and 20-meter subassignments. Changes were at the recent Atlantic City conference. asked in the 50-Me. band to make the first 100 In a review of League finances it was found kilocycles (to 50.1 Mc.) exclusively c.w.; to per that the expenses for the desired promotional and mit n.f.m. 'phone wherever A3 is used (above organizational activities and services to members 50.1); and to permit A0 duplex above 51 Mc. To were exceeding expected revenues, because of give the Class A examination new meaning, FCC constantly increasing costs. To maintain to the is asked to add to it a code examination at 16 fullest possible extent the quality and scope of w.p.m. in addition to the special theory exam. the League's services to amateurs, membership In a far-sweeping decision of fundamental im dues were increased, effective July 1st, to $4.00 portance, FCC is asked to deny a new licensee, in the United States, $4.50 in Canada. during his first year, the right to operate 'phone Two important new committees were set up. on frequencies below 30 Mc. That request would One is to study all possible means of increasing deny future amateurs the present right to begin the efficiency of amateur self-policing within our 'phone operation immediately on the 10- and 11- bands and to make recommendations to the meter bands but would give them c.w. rights on Board for action. The other is a Building Com every amateur frequency and 'phone rights above mittee of five directors under the chairmanship 50 Mc. The Board .decided against asking FCC of Vice-President McCargar to study the de for a compulsory regulation to limit 'phone side sirability of acquiring a permanent Headquarters bands but strongly urged members operating building and its most desirable location. They are below 14.4 Mc. to take immediate steps to reduce also to study the suitability of WlAW to its tasks sideband components more than 3000 cycles from and the feasibility of moving or supplementing its the carrier frequency by at least 20 db. A proposal facilities. They are to make recommendations for to extend high-stability requirements to the 2- desirable actions by the Board, with detailed meter band was studied but it was decided that plans, before the next annual meeting. the time for this had not yet arrived. The by-laws governing eligibility of directors to There was a careful review of organizational .serve on the Board were amended to deny eligi matters, with a considerable emphasis on subjects bility to managers of broadcasting stations. In relating to emergency communication. Funds respect of Director Richelieu, however, who' re were provided for the travel of Section Emer cently so t'hanged his occupation, the Board gency Coordinators within their sections in pro unanimously agreed that he was eligible under . moting and coordinating this work, and provi the wording of the by-laws as they existed at the sions were continued for the travel of SCMs and time of his election, and that it was proper for QSL Managers to near-by conventions. The QSL him to serve out the remainder of his term. Managers got a thumping vote of thanks for their President Bailey and Vice-President McOargar hard work. Proposals for extensive reorganization were unanimously reelected for two-year terms. of the manner of conducting Board meetings and By special arrangement in our Production De of the organization of the Executive Committee partment to hold this page well past the usual and of Headquarters were rejected but .a con deadline, we have been able to get the foregoing stitutional amendment was adopted to permit account of the "high spots" into this issue of holding special Board meetings at the call of a OST. Next month we'll give you the complete majority of the directors. League advertising, minutes to serve as a detailed blow-by-blow ac policies were reviewed and reaffirmed. The pro count of an historic meeting, and the background posal to reapportion ARRL divisions to coincide and details of the Board's decisions will be re with FCC call areas was again examined and ported and made clearer in our next few issues. June 1948 29 NEW FREQUENCY REGS (ii) 3850 to 4000 kc, using type A3 emission, to those stationa locttted within the coutinental limits of the At the special request of ARRL, FCC on April United States, the Territories of Alaska and Hawaii, Puerto 28th, in time for our Spring V.H.F. QSO Party, Rico, the Virgin Islands and all United States possession• shifted our temporary band at 235-240 Mc. to it.'! lying west of the Territory of Hawaii to 170° we•t longitude, subject to the further restriction that type A3 emission permanent location at 220-225 Mc., effective im may be used only by an amateur station which is licenaed to mediately. The old band may also be used an amateur operator holding Class A privileges and then onl.Y through June 8th but thereafter everybody has to wbc.n operated and controlled hy an amateur operator hold move to the new figures. ing Class A privileges. (3) 7000 to 7300 kc, using type Al emission. Users of this band will remember that there is a (4) 14000 to 14.400 kc, using type Al emission, and, treaty arrangement between the U.S. and some on frequeneies 14.200 to 14300 kc, type A3 emission, subject British countries concerning possible use of DME to the restriction that type A3 emission may he used only by an amat.eur stal!ion which is licensed to an amateur in the range 220-231 at certain aviation gateways operator holding Class A privileges and then only when and along the Canadian border. Should inter operated and controlled by an amateur operator holding ference to DME occur, FCC will designate areas Class A privileges. within which the amateur band ,dll temporarily (5) 27.160 to 27.430 .Mc, using types A0, Al, All, A3, and A4 emission and also special emission for frequency revert to 235-240 Mc. for the remainder of the mod11lation (radiotelephone transmissions and radiotele treaty period - until the end of 1951 - and so graph transmissions employing carrier shift or other fre our old band is being held in rP-5erve for that quency modulation techniques), subject to such interference purpose in case of need. We accordingly advise as may result from the emissiona of industrial, scientific and medical devices within 160 kc of the frequencies 27.120 and you to hold on to any 2:35-240 apparatus that is 27.320 Mc. not being converted to the new band, altho no (6) 28.0 to 29.7 Mc, using type Al emission, and on {JRM cases are expected to oecur. • fre,1uencies 28.5 to 29.7 Mc, using type A3 emission. and on frequencies 29.0 to .29. 7 Mc, using special emission Also 011 April 28th, effective at ouce, FCC ex for fre quency modulation /radiotelephone tran.srnissiona and panded our 1215-1295 Mc. band to 1215-1300, radiotele,graph transmJssiona employing carrier shift or per Atlantic City, and simultaneously withdrew other frequency modulation techniques). the right to use pulsed emissions on this band (7) 50.0 to .51.0 Mc, using types Al, A2, A3, and A4 as previously mentioned. ernisalou and, on frequencies ,52.5 to 54.0 11c, special emi.,. aion for frequency modulation (radiotelephone transmissions There is some confusion in our regulations and radiotelegraph transmissions employing carrier shift or where our frequencies and types of emission are other frequency modulation techniques). still stated in prewar terms, with a footnote (8) 144 to 148 Mc, using types A0, Al. A2, A3, and making our actual authorizations dependent upon A4 emission, a.nd special emission for frequency modulation (radiotelephone transmissions and radiotelegraph trans an FCC order in the 130 series - of which there tlllll8ions employing carrier shift or other frequency modula have been about 17 since V-J Day. To clear up tion techniques). this coufusion FCC on April 28th did an editorial (9J 220-225 i\fo, using t.ypes A0, Al, A2, A3, and A4 job on our regulations by issuing a long order that ernission, and special e1nission for frequency modulation (radiotelephone transmissions and radiotelegraph trana repealed Order 130-P and incorporated all our rnissiona employing carrier shilt or other frequency modula present provisions into our standing regulations. tion techniques), provided that until January 1, 1952, if this The only changes in our operating authorizations band is required for distance measuring equipment at cer are those concerning the 220- and 1215-Mc. tain United States gateways and Canadian border locations. amateurs within interference range of those gateways and bands reported separately above, but you should locations shall, after publication by the Commission of an be familiar with all the provisions of the new order designating the areas involved, cease to use this ha.nd, order. Here they are: but shall be entitled in lieu thereof to use the band 235-240 Mc. ,\mendments to Part 12 of the Commission's Rules Gov (10) 235 to 240 Mc, using types A0, Al, All, A3, and erning Amateur Radio Service are as follows: A4 emission, and special emission for frequency 1nodulation 1. F'ootnote "3" keyed to the subtitle "Alloe'lation of (radiotelephone transmissions and radiotelegraph transmis Prequencies" which immediately precedes !12.111 is sions employing carrier shift or other frequency modulation amended to l'P.ad as follows: techniques). until J·anuary 1, 1%2, provided that commenc The assignment and use of a.1.1 frequencies below 25 ing with June 9, 1948, this hand may he used only as a sub megacycles contained in these regulation,, are subject atitute for the band 220-225 Mc in those cases in which the t.o change in accordance with the Commission's final hand 2~0-225 Mc may not be used, as provided in (9), report of allocations below 25 megacycle.a, in Docket above, of this section. Proce.,ding No. 6651. (11) 420-4.50 Mc. using types A0, Al, A2, A3, A4, 2. §12.lli' is amended to read as follows: and A.5 emission, u.nd special emissions for frequency §12.111 Frequencies mm type, of emis:rion for ,,,. of modulat.ion (radiotelephone transmissions and radiotele amateur •tationa. (a) Subject to the limitations attd M1tric graph transmissions employing carrier shift or other fre tioru, set forth herein and in §12.114 .of tbe.se rules. the fol quency modulation techniques). Peak antenna power shall lowing frequency bands and types of emissiona are allocated not exceed 50 watts in order to minimize interference to a.ir attd available for amateur station operation as follows: e.raft altimeters temporarily allocated to this hand. (1) 1750 to 2050 kc. Not available for use. (12) 1215 to 1300 Mc using types A0, Al, A2, A3, (2) 3.500 to 4000 kc. Use of this hand is re.stricted to A4, and A5 emission and special emission for frequency amateur radio stations as follows: modulation (radiotelephone transmisslona and .radio (i) 3500 to 4000 kc, using type Al emission, to telegraph t,ransmissions employing carrier shift or other those stations located within the continental limits of the frequency modulation techniques}. United States, the Territories of Alaska and Hawaii, Puerto (13) 2:mo to 2450 Mc, 3300 to 3500 Mc, 5650 to 5925 Rico, the Virgin lalanda and all United States posse.ssions Mc. 10,000 to 10,500 Mc, 21.000 to 22,000 IIIc, and any lying west of the Territory of Hawaii to 170° west longitude. frequency or frequencies above 30,000 Mc, using on these 30 QST for frequencies types A0, Al, A2, A3, A4, and A5 emission and If you haven't a postwar license, don't forget special emission for frequency modulation (radiotelephone transmissions and radiotelegraph transmissions emplo,ing your 1948 ronewal. See data in this department in carrier shift or other frequency modulation techniques), recent ()STs. and pulse emission. Oprrations in the frequency bands 2:ioo to 2450 Mc and 5650 to 5925 Mc are subject to such interference between 2-!00 and 2450 Mc and between 5775 WANTED: RADIOMEN FOR OVERSEAS and 5925 Mc, respectively, as may result from emissions of industrial. scientific and medical devices on the frequencies A department of the United States Govern 2450 and S8.50 Mc, respectively. ment has need for civilian radio operators and 3, §12.112 is deleted. operator-technicians for interesting overseas •I. §12.114 is amended to read as follows: §12.114 Types of emiasion. (a) Type A0 mmss1on, duty. Men with qualifying experience will be where not specifically designated in the bands listed in selected to operate and maintain radiotelegraph §12.111 of these rnles, may be used for short periu,ls of time stations in various parts of the world, qualifying when required for authorized remote control purposes or for experimental purposes. However, these limitations do not and operating under federal regulations. apply where type A0 emission is specifically designated. The work has particular appeal to radio ama (b) Narrow-band frequency or phase modulation teurs, often calling for the special sort of in may be used, in addition to the types of emission specifically genuity with which hams are endowed. The pay designated in §12.111 of these rules, by certain amateur stations for radiotelephone eommunication until further is good, ranging from $2644.80 for communica order of thP Commission, but in no event beyond August 1, tions technicians to $4149.60 for senior super HJ48, as follows: visors. In those places where the liviniz: costs ( 1) Amateur stations licensed to and operate June~)948 31 setting forth qualifications., particularly with re.spect to the following: 1) Radio operating and technical experience, inrluding military 2) Present code speed 3) Present license(s) and length of time held 4) Part of the world in which duty is desired 5) Part of the world in which duty is not. desired 6) Age and marital status, including number of children, if any 7) Specialized training, e.g., teletype main t.enance, etc. Letters should be addressed to: Box 73, % Administrative Headquarters, The American Radio Relay League, West Hartford 7, Conn. If you have previously written an application for one of these openings, it will not be necessary to write again as your original letter is still on file. POLL RESULTS An article in February QST, entitled "Shall 'Phone Frequencies Be Increased?," published at w ~ ~~~~~~~~~~~~~~~,~ the instructions of the ARRL Board of Directors, Z ~ 000000000000000 0 presented three proposals originated by the Board's Planning Committee and solicited an ~ 1 expression of opinion thereon from all interested ;z; U. S. licensed amateurs for the information of the Board. The poll closed March 31st and the rir sponses were then tabulated for the consideration of the directors in their examination of this matter at their meeting in May. A total of 13,499 licensed U. S. amateurs re sponded. The answers have been sorted by ARRL divisions in the U. S. and the figures are presented in the accompanying table for the general in formation of the membership. NATIONAL CONVENTION We urge you to make your plans now to at tend the big ARRL National Convention at Milwaukee over the Labor Day week-end, Sep tember 4th-5th-6th. It will be the best conven tion in amateur radio in the past ten years. See ~~~~~~~~~~~~~~~1~ the earlier announcement in this department in ~~~~~~~~~~~~~~~ ~ April and May QST. For reservations and further information, write the general convention chair man, Jack Doyle, W9GPI, 4331 No. Wildwood Ave., Milwaukee 11, Wisconsin. FCCommissioner George E. Sterling, W3DF, now "The Honorable," will bring the convention a message from the Commission about the ama teur service. Also from FCC as guests of !,he Milwaukee Radio Amateurs' Club will be George K. ("Red") Rollins, W3GA, chief of the Radio Operator & Amateur Division, and one of his section chiefs, Robert W. Percy, W4IQR, chief of the Amateur Radio Service Section. Between them they will be able to tell us about the FCC administratio_n of amateur radio and answer the many questions that can be expected from the several thousand hams in attendance. 32 OST for 12th ARRL Field Day Coming Up Individuals, Groups and Clubs Preparing for Annual Test on June 12th-13th BY F. E. HANDY, * WIBDI HE Annual ARRL Field Day combines the several hours of dependable service from an many joys of operating ham radio afield ordinary car battery. Such lightweight equipment T· with the more serious business of putting is inexpensive,, easy to service, and a welcome amateur emergency stand-by gear to test. United companion for vacations or long trips. States and Canadian amateurs are again invited A preliminary discussion of the FD rules was to participate in this annual battle with the cle i:,riven on page 62 of April QST. The operating ments, which this year is expected to set new period is 4 P.M. Saturday, June 12th to 4 P.M. records for scores and number of communities Sunday, June 13th, your local -~tandard time. One represented on the air. Naturally, emphasis is point per QSO will be allowed for working either placed on portable operation, but for those home home stations or other portables. Each complete stations that, engage in working the more rugged t,ransmitter-receiver-antelina-power-supply set brethren afield, special listings crediting partici up, where more than one operate simultaneously pation will be published in QST. under one FCC notification, contributes its points Whether your emergency gear is a lone crystal t-0 the group score. The points for each QSO de controlled oscillator run from an auto battery pend on the power level and the source of power and dynamotor or a community affair with gas (battery, generator, commercial mains). Messages driven generator, be sure to give it a FD workout. originated for FD credit must contain the in After all, the fellow who sets up his apparatus formation required by Rule 5 and must be ad and makes only one contact gains in experience, dressed to the SOM or SEO of the ARRL section points and preparedness over the amateur who in which the FD activity takes place. doesn't turn out. Advance reports have it that many of the large clubs have made elaborate Field Day Rules in Detail preparations for this year's fray; however, in the 1) An individual equipment or units placed planning of this contest no opportunity for mak under one call and in control of one licensee -· ing participation attractive even to one- and two one who has made the required -advance notifica person entries has been overlooked. Will you be tion meeting government requirements and who in there helping your local EC put your home is responsible for t,he accuracy of all logs and town on the amateur emergency communications records_ .._ may constitute a score group for entry. map't , Field Day is a test of portables; mobile work does In preparing for Field Day, be sure to select a not count. "Manufactured" contacts arranged site away from any fixed-station location. Make with other stations do not count. FCC §12.92 certain, also, that you file advance notice with requires one notice to the Engineer-in-Charge of FCC of your intention to operate portable at this the FCC district in which portable operation will location. Since every emergency-minded group take place. 1 Give (a) station call, (b) name of ,.,.,ru have precut antennas on hand, the installa licensee, (c) date or dates of proposed operation, tion of antennas should be a routine task. How and (d) location of field-portable. ever, antennas used in the FD must be those put 2) All control locations for equipment operat up especially for the test or antennas maintained ing under one call and re8ponsibility-to-FCC exclusively for community emergency-prepared must be within 500 feet of a given spot for the nf'SS purposes - never any fixed station's skywire. points to count toward one score. It is hoped that FD participation will encourage a) Bands: The following 13 bands (and ad t,hc maintaining in reserve of more easily-trans ditional u.h.f.-s.h.f. bands if you choose) con ported handle-equipped rigs, capable of providing stitute Heparate bands on which simultaneous * <1ommunications Mgr., ARRL. operation rnay be arranged, if desired: .At - 1 Amendment. of the Rules Governing Amateur Radio :1500-4000, 7000-7300, 14,000-14,400, 27,160- Service about May 20th is expected to authorize both 27,430, 28,000-29,700 kc.; 50-54 and 144-148 portable and mobile amateur operation within the continental Mc. ,13- 3850-4000 kc.; 14.2-14.3, 28.5-29.7, limits of the United States on any frequency authorized and available for the amateur service, and at the same time t.o 27.16-27.43, 50-54 and 144-148 Mc. (In Canada remove the requixement for prior written notice to the VE 'phone bands apply.) Engineer-in-Charge if such operation is for a period of less One transmitter may be changed from band to than 48 hours. Watch WIAW bulletins for early information on thia which may eliminate the need for filing FCC , notice band at will for a one-transmitter-class entry. The for Field Day plans as required by current regulations. number of units in simultaneous operation at any June 1948 33 one time determines the class of the entry. It is mercial mains this voids the three multiplier for regarded as improper and grounds far disq·ualifica "independent power source" for points made· lion to u.se mare than one transmitter at one time in while so operating. "In use" is defined as with• the same band, such as one on 3510 and 3700 kc., err battery connected to transmitter o.r receiver. 'You 14.1 and 14.35 Mc., far example. (This is not con can charge batteries 1wl in use from power lines strued to bar the use of two transmitters, one on between periods of transmission or reception. 75 'phone and one on 80 e.w., or one on 7-Mc. For stations in the Northwestern, Pacific, and one on 3.5-Mc. c.w. at the same time, etc., Rocky Mt., Southwestern, and West Gulf Divi for a multitransmitter-class entry. There is no sions, scores may be multiplied by 1.5. distinction between a.m., f.rn., and n.f.m. for Home-station score is the sum of contact FD purposes. Eleven meters will be regarded points plus message credits - Rules 4 and 5. No as one band when using voice, another when multipliers arc allowed. using e.w., as distinct from similar ten-meter A staff Contest Committee will have the final considerations.) word on adjudication of scores and rulings on any V.h.f.-only scores (for work on and above 50 special problems. Field Day results will be re Mc.) will be grouped under one heading in the ported with club entries classified by the number compilation of results. of transmitter set-ups operated at any one time 4) Scoring: Each amateur station worked by a and with credits for nonclub entries as a separate Field Day station counts 1 point. 'l'he same station listing. The summary of points for contacting contacted again counts only (f the FD transmitter stations will have all message credits added befare credit reparted is on a, different amate-ur frequency multipliers. For example: Let's assume that a 25- band as above defined. (In the case of home sta watt rig wholly on batteries contacts 40 sta.tioos, tions, 1 point is credited for each FD portable not originating or relaying any messages. worked.) 4.0 points (40 stations) ,5) Message Credits: Field Day messages. to X 3 (power below 30 watts) (If the re(Juire,ll your SEC or SOM (addresses on page 6) will in 1.20 m1;:~sage orig:inat.f.oC\ clude the number of operators, the field location _?< a (power independent of mains) i• duly sent and· and the number of AEC members in each operat 360 receipted for and' ing group. One such message originated at a Field _>(1.5 (everything on batteries) rnported we then Day station will count 25 points before multiplier, 540 claimed score have subject to deduction of ten points for omission of 25+40=65 XflX 1.5-• handling data and wn points for defects in form. 'i>T7.5 score), To claim credit, message copy must be submitted 7) Hours: Twelfth ARRL FD starts at 4 P.M. with the worked list by bands showing time of each local standard time, Saturday, June 12th, and, contact. Relays: 2 added points before multipler ends at 4 l'.M. local standard time, Sunday,, (1 for receiving, 1 for sending on) may be claimed ,Tune 13th. by FD handling stations. Delivery to addressee is Mail individual and group reports, eliminating; of course required on all FD messages in transit at duplicate contacts, to Headquarters, on or before· the end of the test as prerequisite to credit. ,fuly 9th. Show contact time, band used-:- attach, (Home Stations: 1 point may be claimed for each traffic for claims. Show handling data, power in-· special FD message received and mailed to SCM put, and power sources. Request mimeographed! or SEC with copy to Headquarters. Similarly ARRL forms or make up your own giving the: claim 2 points for FD-message relays, one when information required by these rules, received and one when forwarded by radio.) 6) Multipliers: Powers up" to and including :30 watts input to the final take a multiplier of 3 for COMING CONVENTIONS the points earned. Power limits between 30 and ,June 5th-6th-Atlantic Division, Wash 100 watts, inclusive, similarly take a multiplier ington, D. C. of 2 for the points earned when so operating. Aug. 21st-22nd- West Gulf Division, Independence-of-Mains !Multiplier: Multiply Houston points by 3 when operating with all radio equip Sept. 4th-5th-6th - NATIONAL CON ment independent of commercial power source. VENTION, Milwaukee Battery-Credit Multiplier: The points made Sept. 19th - New Hampshire State, Con for each ccmt.act with transmitter-receiver com cord pletely battery-powered are subject to an additional Oct. 2nd-3rd- Hudson Division, Albany multiplier of 1.5. Charging batteries from com Oct. 2nd-3rd - Southwestern Division, mercial mains while they are connected t,o !,he Los Angeles t.ransmitter o.r reeeivcr voids the indcpcndence Oct,. 8th-9th - Eastern Canada, Montreal from-mains multiplier. Oct.. 16th-17th-Midwest Division, About charging batteries while in use: It is Wichita pr-rmissible to charge from car generator or gas- power, but if this is accomplished from corn- 34 QST for I.A.R. ews favor upon amateur radio, can in no sense be DA CALLS NOT AUTHORIZED deemed guilty of suppressing amateur radio in In recent weeks, there has appeared on the t.oto. In view of these facts, the Headquarters amateur bands a number of stations signing calls feels obliged to announce that, for the time with the prefix DA. The Office of Military Gov being, it cannot handle QSLs either for or from ernment (U. S.) in Germany advises that no DA unauthorized operators in Germany, nor other prefixes are legally authorized for use in t,hat wise sanction their illegal operation. The control country and that action is being taken to identify of bona fide amateur radio in occupied Germany and apprehend the operators involved, all of will be greatly facilitated if amateurs in other whom are believed to be German nationals. nountries would refrain from engaging in com At the present time, we are informed, only the munications with the.se unauthorized stations. following call assignments are authorized in Germany: United States Zone, D4AAA through SWITZERLAND D4ZZZ; British Zone, D2AA through D2ZZ; The Union 8chweiz Kurzwellen ,1mateure, and a limited number in the French Zone from being desirous of maintaining healthy emulation the block D5AA to _D5ZZ. All assignments are among its members· and of strengthening bonds restricted to personnel under military control of with foreign amateurs, has initiated a new oper the individual zones. So far, although represent.a ating award entitled "Helvetia 22." An appro t.ions for restoration of amateur privileges have priate certificate will be awarded to each Eu~o been made by German amateur radio organiza pean amateur, Swiss or otherwise, who subnnts. tions it has not been found in the interests of the proof of having established two-way radiotele Allied governments to permit amateur activity graphic contacts on each of two different bands on the part of German citizens. with amateur stations located in each of the 22 The spirit of amateur radio does not recognize cantons of Switzerland, and to each amateur out geographical boundaries, nor does it engage in side Europe who similarly proves contact with differences arising from opposing ideologies, one station in each of the 22 cantons. political or oth~rwise'. Being truly interna?onally Each QSL submitted as proof must show the democratic, it transcends all of those. things; an abbreviation of the name of the canton, per the amateur is judged by his fellow hams.only by the following: 1, Zurich, ZH; 2, Berne, BE; 3, Lu technical excellence of his signal and the quality cerne, LU; 4, Uri, UR; 5, Schwyz, SZ; 6, Unter of his operating. Those of us who, are privileged wald, NW; 7, Glaris, GL; 8, Zoug, ZG; 9, Fri t,o engage in amateur radio can view with sympa bourg, FR; 10,·Soleure, SO; 11, Bale, BS; 12, thy the plight of those less fortunate who, al Schaffhoruie, SH; 13, Appenzell, AR; 14, St. Gall, though still carrying the spark of the amateur SG; 15, Grisons, GR; 16, Argovie, AG;. 17, spirit and fired with enthusiasm and yearning for Thurgovie, TG; 18, Tessin, TI; 19, Vaud, VE; the privileges of better days, find themselves 20, Valais, VS; 21, Neuchatel, NE; 22, Geneve, denied amateur radio. GE. Nonetheless, the inescapable facts are that the .aforementioned DAs are unauthorized in a coun Contacts must have been made subsequent to try with which there are as yet no peace treaties; 0001 GOT, April 15, 1948. Applications, with ,and that the existing Allied military governments supporting proofs, should be addressed to Inter ,in Germany, because basically they look with (Oontinued on page 11 O) • ·When you hear a signal from Macau_ with a feminine !lilt, it's Teresa Hosario, 2nd op. at CR9AN. Ter".sa, ,better known as Tereng and no relation to the stat10n !licensee, is a top-notch operator with a beautiful fist, .according to the lucky lads who have QSOed her. ·Tereng c;,pies the fast stuff without hatting an eyelash - and does it longhand, too. She is shown here during ,one of her infrequent moments away from CR9AN as ithe nheadliner" of ceremonies in connection with the •inauguration of the Hong Kong-Macau radiotelephone 1service. June 1948 A New Approach to Single Sideband Generating S.S.S.C. by the "Phasing" Method BY DONALD E. NORGAARD,* W2KUJ 1 HE QST article describing a single-sideband exciter operating on the principle of filtering •Here is an outline, with some practical Tout the undesired sideband undoubtedly has pointers, of a method for generating a left many an amateur wondering if all single single-sideband suppressed-carrier sig sideband equipment is necessarily complicated. nal ·without the need for a sharp filter The filter principle is effective, of course, but it and multiple heterodyning. The con1- leads to over-all complexity of a transmitter and plete practicability of the system has requires very careful design, construction and ad been proved by almost two years of laho justment. In fact, to set up such a transmitter and ratoi:y and on-the-air testing by the make it work properly is a task that requires con author. It is a significant step in taking siderable technical skill and meticulous attention s.s.s.c. out of the luxury class and plac to detail. The few who have done this job. well ing it within the reach· of every amateur. deserve to be complimented. On the other hand, the advantages of s.s.s.c. over a.m. are too great to be passed over by any and better performance can be obtained at much amateur looking for something better in 'phone lower cost. Fundamentally, the method consists technique. Some of these advantages have been of removing one of the sidebands by means of a balancing process rather than by filtering. Upper Sideband The principle employed may be explained by reference to Figs. 1-A and 1-B, which are vector diagrams showing the relationship between car Lowtr rier and sidebands produced in amplitude modu Sideband Upper lation. In Fig. 1-A a carrier is shown in "refer Sideband. ence" phase, and the positions of the sideband C11rrief La,&inf / 11 vectors indicate that peak-envelope conditions Reference•Phase exist at the instant shown. In Fig. 1-B a carrier farrier of by 90' - Reference• Ph..., of the same frequency but 90° away from that of Fig. 1-A is shown. The two sideband vectors in Lower Fig. 1-B indicate that the envelope has a value Sideband (at the instant shown) equal to the carrier; that (A) (BJ is, the modulating signal is 90° away from that Fig. l -The carrier and sideband relationship re which gave the conditions shown in Fig. 1-A.8 quired to generate a single-sideband sign'al by the If the conditions shown in Fig. 1-A exist at the "phasing" or "balancing" method. The modulating output of one modulating device at the same signal in B leads the modulating signal in A by 90°. When the two signals represented by A and B are com instant that the conditions indicated in Fig. 1-B bined, the upper sidebands add and the lower sidebands exist at the output of another modulating device, cancel out, resulting in a single-sideband signal. and if the sideband frequencies and magnitudes described in previous art,icles in QST, and Table are the same, the simple sum of Figs. 1-A and 1-B 1 shows a comparison of some of the features. will consist of carrier and upper sideband only. These points were discussed in detail last month.2 It can be seen that the lower-sideband vectors are equal in magnitude and opposite in direction, S.S.S.C. by "Phasing" and hence would cancel one another. How can Fortunately for the rest of us, another method this result be obtained in practice? of generating single-sideband signals has been The vector diagram of Fig. 1-A might be said developed to a degree that many of the problems to represent the output of a modulated amplifier associated with the filter method are eliminated, where a carrier of reference phase is modulated by a tone of reference phase. Thus, Fig. 1-B * Research Laboratory, General Electric Co., Schenec tady, N. Y. would represent the output of a second modu 1 A. H. Nichols, "A Single-Sideband Transmitter for lated amplifier where a carrier of the same fre Amateur Operation," QST, January, 1948. quency but 90° displaced from reference phase is 2 D. E. Norgaard, "Wb».t About Single Sideband"/" QST, modulated by a tone that is also 90° displaced May. 1948. 3 For interpretation of these ve.ctor diagrams, see QST for from its reference phase. To make the whole thing May, 1948, page 14. work, the frequencies of all corresponding signals 36 QST for represented in the two vector diagrams must be to a higher frequency is not at all· necessary as nxactly the same. This would suggest an arrange is the case when a filter is used to eliminate one ment such as Fig. 2, which would operate satis 1sideband. faetorily-if the 90° phase-shift. d,wices held ampli 2) Conventional parts may be used in any an June 1948 37 .,. ... ··• TABLE II A Practical Exciter Circuit Values £or Use with Fig. 4 While i,he block diagram of Fig. 3 is useful in - explaining the principle of generating single- ,~vmbol fL Network /3 Network Rerrw.rk., sideband signals, it does not represent a complete single-sideband exciter with enough gadgets to Rt 51,000 ohms O.!Omegohm Adjust RC product to - 12.ao microsee. for -:t., satisfy a person with a practical turn of mind. ('1 241 µµfd. 512µµfd. 51.20 rnicrosec. for /3. There is little to be gained by using single side Tolerance: =- }.,~('.:('. band unless the carrier is attenuated, but l<'igs. ------· R2 0.10 megohm 0.56 megohm Adjust RC product to 1-A, 1-B, and 3 do not indicate this. Therefore, 148.5 rnicrosec. for °'• Fig. 6 is offered as a workable system that pro C2 1485µµfd. 750µµfd. 420.0 microsec. for /3. vides for carrier attenuation, amplitude modula Tolerance: = ½~C. ---·· tfon, phase modulation, single sideband, opera Ra 0.56 megohm IJ.56 megohm Adjust RC product to tion on 75- or 20-meter 'phone, and QSY within --- 1230 microsec. for «, these bands. If multiband operation is not desired Ca 2200µµfd. 9140µµfd. 5120 microsec. for /3, and if QSY 4 is not deemed necessary, modulation Tolerance: ::1::: ~j(;.{,. ---· can be accomplished at the operating frequency Rio 2,2 megohm 2.2 megohm lnpu t eircui t may be by appropriate simplification of the arrangement ····-- omitted if driving cir- of Pig_ 6. C10 0.05µfd. 0.05µfd. cuit supplies grid return. ----- It is not the purpose of this article to give Rua, b 1000 ohms 1000 ohms R('.sistors a and b in specific drcuit-design data for a complete single each section ehould be sideband exciter; rather, the purpose is to point Rt2a,b 2000 ohms 2000 ohms matched to within= out the over-all features that mu.~t be observed ½%- in order to satisfy the requirements of this system Rtaa, b 3000 ohms 3000ohms of generating single-sideband signals. Por in Rua, b 4000ohms 4000 ohms · 10% tolerance suitable. stance, the design of t,he bandpass drcuits indi cated in Fig. 6 is beyond the scope of this article. B + = 300 volts. All resistors are ½-watt composition. For sake The advantage of using such an arrangement de of stability R1, R,, &, Rn, R12, Ri, and Ru shouid be high-quality signed to cover the amateur band in use is that reaistoro. Continental "Nobleloy" Type X-½ resistors are recom- no tuning adjustments whatsoever need be made mended. c,, c. and c, should be made up of fixed mica and com pres- sion padders in parallel to permit adjustment of RC products to when it is desired to QSY. With ordinary circuits, agree with close tolerances in "Remarks" column. best, operation usually demands retuning when Tubes used: two 6SL7GT double triodes for each network. Maximum signal input: 2 volts peak-to-peak. Source of Insertion loss: approx. 8 db. for each network. modulallnt ,ignab quency range of at least 7 octaves, or from 60 to 7000 c.p.s., for the constants given. Of course, the ideal differential phase shift is exactly 00°, and Single-sideband the excursions of the actual phase-shift curve arc output •2° from this value. The ratio of undesired side- band to desired sideband is dependent upon this deviation, the most unfavorable points being at the peaks and valleys of the differential-phase- shift curve. The ratio Audio- undesired sideband = tan (~) 2 ' desired sideband Fip.. 3 - The system outlined in fig. 2 becomes and for a = 2°, practical by using two audio channels (o: and/l networks) with a constant phase difference of 90°. =tan([)= 0.0174, or -35 db. large percentage changes in frequency are made. The symbol o represents the defiation of the However, ordinary tuned circuits can be sub actual performance from the ideal 90°, and, in the stituted for the bandpass transformers, as in any above example, awas taken at its maximum value. transmitter. The average attenuation of the undesired side- A conservative output rating for an 807 output band is more than 40 db. over the band of modu stage would be 30 watts peak, under drive condi lating frequencies between 60 and 7000 c.p.s. tions where the grid takes no current (Class AB1), There _is little to be gained by improvement of This will compare in sideband power to an a.m. this ratio, since subsequent amplifier distortions signal of 60 watts carrier output. If suitable bias can introduce the unwanted sideband in sufficient 4 By "QSY" is meant any change in frequency, whether obtained in discreet steps (by switching erystale, for exam amounts to mask any improvement gained by ple) or continuously-variable frequency control by mea11S of idealizing the phase-shift network characteristics. aVFO. 38 OST for e•o------~----~-----1 • l Most microphones in current ~R, ~R amateur use require low-level am- 31 141 c3 ~ plification (the usual microphone preamplifier) to bring their output / signals up to, say, a level of one or _ -pull two volts .. This is the job required \D ·put of the audio amplifier ahead of the t---° oc and {1 phase-shift networks. (See Input Fig. 6.) R12 R2 JR b 14b . This is as good a time as any to oo--t--"------'~'------'~ mention the desirability of includ- ing in the "preamp" a bandpass Fig. 4 - A typical 3-clemcnt o: or /3 phase-shift network. Values are or low-pass audio filter to pass the given in detail in Tab!~ II. important speech band out to 3000 cycles or so, to conserve space on and drive are supplied to the 807, a conservative the bands. The operation of the rest of the .50 watts peak output may be obtained. This, of eircuits in the system in no way requires this, course, is the power equivalent of 100 watts but good sportsmanship in the use of our bands carrier output of an a.m. signal. In either case, does. It is good practice to eliminate unneces the output power is sufficient to drive additional sary low frequencies, too, eoncentrating on amplifiers of fairly-sizable ratings or to use the portion of the audio spectrum between 200 directly as a low-power single-sideband 'phone and :3000 c.p.s. for maximum intelligibility. transmitter. In comparison, only 15 watts 6 of Numerous articles 6 have been written on the carrier output can be obtained when using a.m., subject, and suitable bandpass-filter designs are or 40 watts 6 with phase modulation. available for this purpose. Why do anything It is usually practical to build the voice-fre about it at all, if the system as such does not re quency equipment (the a.f. amplifiers and the quire it? The answer has two important aspects phase-shift networks) on one panel, and the ··- important to you as an occupant of the bands modulators, converter (if used), and amplifiers we share: including the 807 output stage on another. The 1) Intelligible speech does not require trans dashed line in Fig. 6indicates such a division and mission of frequencies higher than :3000 c.p.s. To gives us a chance to consider these portions sepa do so adds practically nothing to intelligibility rately. The functiona,l block diagram (Fig. 6) might appear formidable at first glance, but the whole arrangement lends itself to rather simple circuit design. Separate consideration of the two portions of Fig. 6 should not, be I J taken to indicate independence of one from l 4oo· the other. It is well to keep in mind that in t:=::,:t:::::):::::=l=:::::::~~t:"~~~T,l:E _ 90• ~ 3 this system the audio-frequency circuits a.nd : oo· ,, 80• il! the radio-frequency circuits must work 51 l. hand-in-hand in order to generate single- j 20° sideband signals of superior quality. One Notes on the Audio System Octave The audio-amplifier and phase-shift cir 8 10 32 84 128 251 5f2 cuits are straightforward. 'rhe important Frequency R,tio consideration is that the phase-shift and · /i'ig. 5 -·- This plot shows how the 90° difference between amplitude relationships determined by the the o: and fJ networks is maintained over a wide frequency range. The scale for the phase difference is given on the right-hand side phase-shift circuits must be preserved over of the graph. the entire voice range in succeeding parts of the system. Fortunately, there is nothing but does increase the space in the band required difficult about it, once the objectives are clearly for transmission. It boils down to the fact that in mind. These objectives are: we w11,nt the "other fellow" to use as little of our 1) Low harmonic distortion and noise. bands a8 possible, and the Golden Rule certainly 2) Vanishingly small discrepancies in phase- does apply in this matter. In addition, regardless shift and amplitude response. of how "high fidelity"-minded one may he, :3) Ease of control and adjustment.. 6 W. W. Smith, "Premodulation i:lpeech Clipping and 4) Simplicity and low cost. Filterini,:," QBT, February, 19411; J. W. Smith and N. H. Hale. "Leo's Not Overmodulate," QBT, November, l!J16; 5) St.ability of characteristics. W. W. Smith, "More on Speech Clipping," QBT, March, 1947; Galin, "Audio Filters for the Speech Amplifier," QST, 0 RCA ratings for this class of service. November, l!H7. June 1948 39 crowded bands force the operator who listens to 6) Provision for adjustabic carrier level; gen the transmission to restrict his receiver band eration of a.m., p.m., and single-sideband signals: width so much that he receives onlv what is output-level control. nece.,;sary, if even that much. Not only is "high 7) topfamal features) Operation on 75- or 20- fidelity" wasted, but also its us(e is downright meter bands; easy QSY within each band,; choice selfish. of sideband transmitted. 2) Elimination of frequencies below 200 c.p.s. Obviously, a number of methods exist for 11,c rnmoves a large percentage of the high-energy complishing these objectives. Many of the pos speech components that do not cont,ribute to sible methods that may occur to the designer will intelligibility. Such elimination permits the trans satisfy the requirements quite well; some will not. mitter to concentrate its efforts on onlv the essen Others, while technically adequate, may be diffi tial portions of speech power. In pr;,ctice, this <.mlt to adjust or may be impractical in some other means something like 3 to 6 db. in system effec way. Since the handling of radio frequencies is tiveness. Remember how we gained 9 db. by concerned in this portion, good mechanical layout eliminating the carrier (corresponding to zero and construdion is of considerable importance. ------A.F. SECT~N-1-R.f. Also, since st.ability of adjust ment is one of the principal Microphone Preamp. object.ive.s, it is a good idea to 200-3000 -----X, CP.S. Disabling Switch provide some sort of lockin11: (Disable for P.MJ arrangement for the balance controls to prevent accidenttil Rhi.fting of their positions. Mic. Gain Control Balanced Modulators Fig. 6 indicates the use . of two balanced modulators. The balanced modulator is not a new idea - in fact it is one of Cmiel Level Cont. the oldest modulation schemes ----x, in existence - but such a thing Disabling Switch is not often employed in ama (Disable for AJ.4.) Output . tcur practice. A little explana tion might be helpful in un derstanding whv and how balanced modula.tors are used. In amplitude modulation the maximum strength of any side band that can he produced is one-half the Rtrength of the Fig. 6 _,,, Block diagram of an exciter capable of generating s.s.s.c., a.m. anJ ,:•arrier.2 Since the carrier must p.m. signals on either the 75- or 20-metcr bands. Table 111 giveR a dcseription be present in order to be modu of the various components. lated, but is not needed after- modulation frequency) and one sideband, 2 on the ward (in single-sideband trans- basis that these components were not essential'? mission, that is) it can be balanced out. This, Two or three dollars spent on a suitable audio then, is one job that the balanced modulator filter (and that's all one should cost) can give a is called upon to do - namely, to permit side transmitter a communication effectiveness equiv bands to be generated, but to balance out the alent to doubling or quadrupling its output carrier after it has served its purpose. There are power. It's worth it! many forms of balanced modulators: some bal ance out one or the ot,her of the two signals sup Notes on the R.F. System plied; others can balance out both input signals. Considerable flexibility is possible in the design But none of them can balance out onr. ~i,leband of the radio-frequency portion of the block dia a,nd not the other. Nature itself seems to be quite . gram in Fig. 6. The objectives in this portion of positive about that. But while balanced modula the single-sideband system are: · t,ors may be new to amateur radio, there is nothing 1) Very high order of frequency stability. difficult about their construction and adjustment. 2) Provision for !)0° r.f. phase shift in the ex- Since the signal that is to be balanced out is an citation for the two balanced modulators. alternating-current wave, it is necessary in the 3) Ease and stability of adjustment. proceSR to· take account of phase relatioi°i.ships as 4) Absence of r.f. food-back. 1vell as magnitudes. Unless the two signal::! which 5) Low distortion in modulation and subse are to pe balanced have a phase difference of quent amplification. exactly 180°, perfo<'.t balance cannot he nbtaincrl 40 QST for by lilly amount of adjustment of amplitudes alone. This, incidentally, may explain why trou TABLE III ble is sometimes encountered in neutralizing an Explanation of Fig. 6 amplifier, since the same principle iR involved. Mirrnphonp, pri'.amplificr Sufficient. gain to bring microphone Jn the ease of the balanced modulator, the per output to " voltage level of approx. fection of balance required is usually quite high, 2 volts. peak-to-peak. and some means for satisfying t,he eondition.s a,(J Phase-shift networks in accordance necessary for balance must be provided. Vcry few with Pig. 4. Two 6SL7GT tubes. :irrangements automatically provide the .condi A.P. amplifier Push-pull self-balancing amplifier with good phase and amplitude char- tions necessary for perfect balance and frequently acteristics. Maximum output required those that do arc limited to operation at low fre approx. 2 volts, peak-to-peak. qucncie:;, where circuit strays have negligible Balanced Modulators 1 •rwo 6SA7 tubes (in each). effect. It has been found practical to "grab the and 2 See Fig. 7 for details. bull by the horns" and use some aiTangement Carrier phase-shiftrr, 711 5-Mc. double-tuned transformer with where separate phase- :md amplitude-balance ad push-pull output from e,ach winding justments are provided, rather than to hope for at low impedance. Output on each line 2 volts, peak-to-peak. a fortuitous set of conditions that might permit balance. Carrier amplifier 6SJ7 tube. The circuit shown in Fig. 7 illustrates th.is T2 .5-Mc. double-tuned transformer. philosophy. .Fundamentally, only one <)f the Disabling switches Bias controls for No. 3 grids of modu lators. Can be ganged to permit tubes need be supplied. with modulating signal, s.s.s.c.-a.m.-p.m. two tubes being necessary only to allow balance Carrier-level control Bias control on grid No. 1 of carrier of the undesired component (the carrier) in the amplifier. Minus 10 volts to minus 3 output. If, however, each tube is made to generate volts range. :,,'idebands as well as to balance the carrier from Bandpass double-tuned transformers the other, the ratio of residual unbalanced carrier to cover 75-meter 'phone band. ;;ignal to desired output is made smaller at low Bandpass double-tuned transformers cost. Likewise, even small amounts of the modu to cover 20-meter 'phone band. lation defect known as carrier shift are effectivelv Frequency converter 6SA7 converter tube. reduced. The carrier signals at, points _A and B R.F. amplifier No. I 6AK6 miniature beam tube. Operates in Fig. 7 are made as nearly equal in magnitude as Class A amplifier. and opposite in phase as is feasible using circuit R.F. amplifier No. 2 807 beam-power output tube. Can be components of ordinary commercial tolerances. operated as Class ,\ or B amplifier. The JW circuit between point A and grid No. 1 nf the first modulator tube (a 6SA7 converter ~.ibe in this example) may be designed to provide applied t.o the tubes. No attempt is made to about 20° phase shift at the operating frequency, equalize the mal,!;nitudes of the signals in the grid by suitable choice of R. and C•. The RC circuit circuits because it is almost too much to expect in the other. grid can be designed to produce th.at a perfectly-balanced pair of tubes could be variable pliase shift from 10° to 300, by adjust found in order to take advantage of balanced ment of the trimmer capacity, Cb. This permits amplitudes. Instead, the function of amplitude a phase correction of ± l.0° ------· usually sufficient balance is accomplished by means of a bias ad to insure perfect, phase balance of the signals justment on one of the tubes of the pair, so th.at the carrier signals are balanced out in the plate circuit of the tubes, That, incidentally, is what must happen anyway, regardless of the method used. The picture is completed by applying push pull modulating sigrials to the No. 3 grids so that the sidebands produced by the separate modula tion processes in each tube add together in the common plate circuit. The audio-frequency com ponent balances out in the plate and screen cir cuits, this being a case of a balanced modulator that balances against (',ach of the input signals. However, slight unbalance of the audio-frequency signals does absolutely no harm in the particular Phase Balance/ - application of this circuit, so no provision is Con1rol - made for balance adjustment at low audio fre quencies. Fig. 7 - A typical balanced modulator, nsing 6SA 7 In any balanced modulator the efficiency is tubes. Provision is included for obtaining amplitude and necessarily low, since at least one of the input phase balance of the r.f. (carrier) input. signals is dissipated in the modulating elements June 1948 41 or associated circuits. In the case of a balanced simply, too) with a carrier-locking arrangement modulator that suppresses the carrier, the effi that requires only a small amount of transmitted ciency cannot possibly be greater than 50%. The carrier to keep the locally-generated carrier abso efficiency obtained in practice is more like 5% to lutely synchronized with that from the trans 10%. Where two balanced modulators are used mitter. Jt has been found that a carrier level 20 (as in Fig. 6) the efficiency is still lower, since the ALBERT E. HAYES, JR.," WlIIN N recognition of the valuable emergency work munity plan of the ARRL Emergency Coordina done by amateurs in the past, and in view of tor for its community, and that the spirit of I the increasing coverage of the country by the coiiperation resulting from the active participa ARRL Emergency Corps, the Western :Union. tion of t,he wire company in this program will Telegraph Company has reinstituted its co put the AEC in the best possible position to be operative program whereby their Office Mana of assistance to our country "when the wires gers· and Superintendents, distributed through are down." :,;ome 3500 communities, will contact local ama It is interesting to note that during the pre teurs and amateur clubs, with a view toward war operation of the plan, amateurs participated better liaison between WU and amateurs in time in eighteen emergencies during which 144 opera of emergency. tors assisted Western Union and, as a gesture of Under the arrangement the amateur is pro appreciation, were awarded the company's vided with new opportunities for enlarged traffic certificate of public service personally signed by experience in time of emergency as the result_ of its president. improved understanding by Western Uruon personnel of what amateurs can do, as an accom Join the Emergency Corps Today plished group of communicators, when duty calls. ARRL earnestly urges every amateur not By this same token, the wire service benefits by already registered to send a card or message to acquiring a competent outlet for its top-priority ARRL for a Form 7, to get one from any League disaster traffic, the dispatch of which is essential official, or to ask for one at the nearest Western for the prompt restoration of its facilities so Union office. It is important to the amateur serv t,hat the resumption of normal service may be ice to be able to tell the PCC and the Red Cross accelerated. that many of us are in the organized Emergency To further the collaboration between the Corps. It isn't necessary to be a League member League and WU, James D. Felsenheld, W2IM to belong. By whatever route, get lined up with \formerly W2GA and W3MI), has been ap the ARRL Emergency Corps today! pointed WU director of amateur radio relations, Western Union has agreed to take part with ,vith headquarters at 60 Hudson Street, New others in expanding the Corps, by promoting York. Instructions have been issued to all West reasonably among Uil.!l,ffiliated operators the idea ern Union superintendents and managers to of registering their facilities as a preliminary to make ARRL application forms -available to receiving t,he ARRL card that identifies them amateurs desiring to join the AEC, and to extend with the League's Emergency Corps. For that every courtesy to t,hose interested in the handling purpose, the WU offices will have the familiar nf public traffic. Radio clubs in the larger cities Form 7 registry blanks, available to all lhmsed may feel free to call upon the local Western radio amateurs, to align them with the Corps. Union representative to address their meetings These blanks will be routed by WU to ARRL. and thus gain interesting knowledge of the ad As soon as recorded, and the applicant informed, vancements being made in wire communications. the blanks go to SCMs (and local coordinators It is hoped that, before long, each Western where appointed) so complete organization in Union office will have been written into the com formation is available at three points in case of ii}fational Emergency Coordinator, ARRL. emergency. June 1948 ·43 A Transportable 10-Meter Beam For the Man Who Has To Move Periodically BY EMMETT P. BONNER,* W4MXP ANY hams who have to move from time to Erhorn 1 for maximum gain --- 0.15 wavelength time hesitate to erect a rotary beam, and spacing for the director and 0.20 for the reflector. M so have to content themselves with indoor The clement lengths given in the referenced arti- antennas or fixed outdoor wires. The writer, being . cle were used without further tuning. In order to in the Navy, was in that category, but finally make use of the inexpensive Twin-Lamp standing took the bull by the horns and worked up a light wave indicator, • 800-ohm Twin-Lead was used transportable beam. It is hoped that its construc for the feeders. A "T"-match was used, adjusting t.ion may suggest ideas to other hams similarly it by trial-and-error until the top light of the indi situated. cator was completely out when the lower light The emphasis in this article is on mechanical was at full brilliance. Using 1-inch diameter construction. The boom alone weighs 4½ pounds aluminum tubing for the clements and the "T" while the complete beam, including the elements, match, the spacing for the clamps was 24 inches weighs 16 pounds. Wind resistance is reduced to a for 28.6 Mc. This will probably vary, depending on the spacing between the "T"-match and driven element (2 inches in this case) and the relative sizes of the tubing used. The Pipe Mast The mast is made of water pipe supported by three guy wires, and is 86 feet high. The pipe was begged, borrowed and bummed from wholesale plumbing-supply houses and scrap piles. The lengths are 12 feet, or less and all joints are treated with pipe-thread compound so that the sections can be disassembled. The lower section,'! are 2-inch pipe, tapering to l½-inch pipe about half way up. The final foot or so is %-inch pipe, the reducer at this joint serving also as a bearing sur face for the guy-wire bearing. An earlier version of the mast used 1-inch pipe for the top half, but the pipe was unable to support its own weight horizontally and broke at the threads while being erected. The 1 %-inch pipe has thicker walls, leaving sufficient metal after the threads are cut. The guy-wire bearing is an iron disk with a hole in the center to pass the %'.-inch pipe, and Tho mast and beam rotate as a has three small holes 120° apart near the rim to unit in a guyed bearing at the top. take the guy wires. 'The edges of these holes will mimimum by the small silhouette area presented. shear through the guys (the writer found out the Wire braces permit using light and cheap alumi hard way) unless thimbles, sister hooks, or chain num angles, and also provide 1tn easy way to links are used. The disk rotates smoothly on the correct any horizontal misalignment of the ele reducer between the %'.-inch and 1½-inch pipe. ments. The mast and beam can be dismantled The guy wires are made of cheap No. 12 galva into lengths of not over 12 feet and bound to nized iron clothesline wire, and are broken at inter gether to form a compact unit for moving. vals by porcelain strain insulators. Two guys were The design features of the beam were taken attached to the roof edges in this case and the 100% from QST and the ARRL Handbook. Wide third was led down at about a 45° angle to an spaced "plumber's-delight'' construction was iron-pipe stake in the ground. employed, using the spacing rnnommended by A .lower bearing was constructed at the roof edge, in the form of a strong wooden box nailed * 21 Holloman Road, RFD No. 1, Falls Church, Virginia. to the side of the house, The box was notched to ! Erhorn, "Element Spacing in 3-Element Beams," QST, pass the pipe, and a metal strip screwed across October, 1947. "Wright, "The Twin-Lamp," (JS2', Oct,,ber, 1947, and the n:otch afte.r the mast was in place. fn lieu of 'l'he Radio Amsteur'a Hani//JQok, p. 494. the box bearing, a second bearing similar to the 44 QST for guy-wire bearing could be used with a second set of guys. Beam Elements and Support The elements can be made of any tubing avail able. This beam uses 12-foot lengths of I-inch o.d. aluminum tubing, H6-inch wall, with ½-inch o.d. sections telescoping in the ends. The boom is made of two parallel aluminum angles 6. inches apart, screwed at both ends to a 2 X. 2 wood block. The angles used were 1 by 1 by ¼ 6 inch, and crune in 16-foot lengths. The excess lengths (about 4 feet each) were fastened alongside the regular lengths at the center of the boom to make it, more rigid. The center support is 6 by 11 by 1 ½ inches (two %;-inch boards nailed together will do nicely), with two %'.-inch pipe flanges bolted to gether through it from opposite sides. The exact location of this center support with respect to the boom should be determined by balancing the boom with the elements lashed temporarily in place; it will be about 5½ feet from the forward A close-up of the aluminum-angle boom. end of the boom. After the center support is at- . tached with screws, the elements are attached by parallel angle stock, on the other hand, is ex means of metal straps about 1 inch wide. The tremely well suited to painless attaching of the straps holding the director and reflector are made elements. Furthermore, the ahgles cost about $2 a little longer on the inner ends, and an extra hole all told, against $5 for the tube. Putting It Up The feeders were led up through the mast as it was assembled, entering and leaving the mast through small slots cut with a hack saw.3 They could be led up outside the mast, but tend to foul the guy wires when the mast and beam / rotate together. ,:,/ Raising the beam is the most complicated .,<"'"'. part of the whole business. The method used was .4"· to lift the mast onto a temporary support-2 X 4s /' nailed in the shape of a)arge "X" with a third 1/,,,,,,~'" board nailed across the bottom to keep the sup port from spreading -·- then, holding the beam perpendicular to the mast, the mast was screwed li'ig. 1 -- The simple construction of the 3-element into the bottom flange. .After the beam was beam is shown by this outline drawing. Dimensions and constructional points are discussed in the text. tightened in place on the mast, the guy wires were connected to the disk and the foeders were con is drilled in each strap to provide points for nected to the "T"~1natch. A simple wooden mast attaching the bracing wires. A 15-inch length of step was made to keep the mast from digging into %-inch pipe is screwed into the upper flange and the ground. At this point the neighbors were drilled at the top to provide a point for attaching called in to help swing the completed beam and the upper ends of the braces. Small turnbuckles mast into its final position. Lowering the beam were inserted in the bracing wires to permit cor could conceivably be done by one man, using a rection of minor misalignment of the elements. block and tackle. This type of boom was found to be far simpler This particular beam is screwed into a pipe to use than a 2-inch aluminum tube previously flange which is welded to the top gear of a surplus tried. :Bolting or otherwise attaching the elements propeller-pitch motor, but it is suitable for to a tubular boom is a rather difficult task, be practically any system of rotation, including hand cause the elements do not tend to remain hori zontal or parallel to each other. Notching a 3 Running 300-ohm line through small-diameter pipe i• t.ubular boom so that the elements are parallel likely to affect its characteristic impedance and make it impossible to eliminate standing waves. Coaxial cable would requires precision work and also weakens the be better suited to this type of mounting, but should be boom. (Our first beam broke this way.) The provided with a "bazooka" at the antenna end. - Ed. June 1948 45 25 Yea. rs Ago 'YhoneJGnd l>llunnies this month ''WIRELESS NoRTH Pm,E-·-NEXT!" Thus ,June 1923 QST sets its sights on the next target of our ar!complished DX-chasing hret,h ren: ARRL Publicity Manager "Jake_" B_ollP;s enthusiastically tells of our Board of Direction s approval of arrangements worked out bet~een President Maxim and Dr. Donald B. MacM~, noted explorer, for amateur two-way commumca tion with the schooner Bowdoin during tJ:us ye:1'1''s expedition to the Arctic Circle. Quest10~es are now being eirculated to select a qu~li!ied amateur to represent ARRL on the rn1ss1on. Listen for WNP- Wireless North Pole! The books have been officiall:v, closed on t}1e PORTRAIT overwhelmingly-successful Third Transatlan~1cs Ol= A l'I-IO/.llaftC with publication this issue of the formal reception Al 46 QST£o.r ,,...... ~,World Above 50 MC. CONDUCTED BY E:P; TILTON,* WlHDQ ITH the 50-Mc. gang still waiting for the first major opening of the spring DX WE CHANGE TO 220 MC. Wseason as April came to a close, the 2-meter Shift from 23S to 220 Mc. Effective band steals the headlines in the news of the April 28th. month's v.h.f. activities. While nothing approach ing a new record for 144 Mc. was worked, the As detailed elsewhere in this. 'issue, number of contacts made at distances beyond the anticipated shift of our 1¼-meter band 200 miles during April, a month when operating from its temporary assignment at 235 to ranges are only beginning to stretch out, gives 240 Mc. to the permanent allocation at · some indication of what may be expected in the 220 to 225 Mc. was announced by FCC on best months for tropospheric DX now just ahead April 28th, effective at once. In order to of us. provide ample time for changing over to The North Atlantic Seaboard DX season offi the new band, the 235-Mc. band will re cially opened on the evening of April 19th, when main available to amateurs until midnight, VElQY, Yarmouth, Nova Scotia, worked a string June 8th, and both assignments may be of Wls and W2s. A pronounced skip effect was in used until that time. evidence, with W2s in the region around New Subject to the remote possibility of in York City coming in strongly, while Wls in terference to certain distance-measuring Connecticut, Rhode Island, and on Cape Cod devices employed on aircraft of foreign were much weaker. Boston-area stations, still countries, the 235-Mc. band will be held nearer Yarmouth and with only water inter for amateur 11Se in such areas as inter vening, were not heard at all by VElQY, and ference to this service might dictate. Other the few in this region who heard him reported his wise all operation by amateurs in the 235- signals weak at be,st. 240-Mc. band will cease after June 8th. Between 8:15 and 11 P.M. on the 19th., VElQY worked W2BA V, Bedford, N. Y., WlSF, Bran ford, Conn., WlDAH, N. Scituate, R. I., W2MO, 6 to 7:45 CST, with LUs and OXs coming Livingston, N. J., W2NPJ, Elizabeth, N. J., t,hrough with a rapid flutter, but with quite strong W2NLY, S. Plainfield, N. J., W2MLF, Fanwood, signals. More rarely, the band opened around 3 N. J., W2BLF, Newark, W2SVI, New York City, P.M., and then the signals sounded more like DX W2NGA, Bronx, N. Y., W2UPY, Patterson, Rignals do on 10. On April 3rd such an opening N .•J., and W2WLS, Farmingville, N. Y. Signals lasted from 3:45 to 5:30, during which LU9EV heard included WlPBB, W2MCG, WlDHX, worked 3 Mexican stations and XElKE worked W2KDX, W2QUF and WlBCN. The most dis 8 LUs and CX3AA. The band reopened with the tant of these, W2NLY, represents a hop of some eustomary fluttery signals from Argentina at 450 miles, with the Boston area (and its hundreds 6:55 P.M. of 2-meter stations) almost directly in the path at On other South American paths the DX showed a distance of only about 275 miles from Yarmouth. some tape1ing off from March levels, but stations On 6 the news is still mostly from the Latin in Peru, Surinam, Brazil, Argentina, Chile and American countries, though unquestionably the Uruguay were still finding the band open at fairly spring season's big doings will have been well frequent intervals, mostly during the evening underway in this country before this department hours. During the evenings of April 4th and 5th reaches its customers. Some idea Q.f the reliability KP4AZ heard LU9EV, LU5CK, and several other of the Mexico-to-Argentina 50-Mc. circuit can be signals of Spanish-speaking stations. gained from the record of XElKE, who reports The South Atlantic has yet to be bridged two that from February 18th to April 28th there were way on 50 Mc., though it i:; established that the only six or seven days when he did not work or path between South America and South Africa hear LlJs, and even on some of these days the ha,; bL-en open on several occasions. OElAH heard band may have been open! There were two dis the Hignal of ZSlP when the latter was testing tinct types of openings, the most common being with G5BY, and ZS6GX heard CElAH when the almost nightly one which developed around Ida was trying to raise ZSlP, but no two-way * \'.H.F. Editor, QST. work has yet been done. The m.u.f. along that June 1948 47 characteristic aurora fuzz. When it went off Ted RECORDS ealled CQ on c.w. and the signal came back again, still on 'phone and unreadable. After several Two-Way }Vork tries the signal faded out. Has anyone else had 50 Mr..: CE1AH-J9AAO similar experiences on 144 Mc.? l0,500 Miles-October 17, 19U 144 Mc.: W3GV- W0WGZ V.H.F. Doings at the National ARRL 660 Mile• - September 111, 1947 Convention 235 Mc.: WlCTW -W2HWX 210 Miles - October 12, 19-17 For several months the Milwaukee Radio A1.na 420 Mc.: W6VIX/6 - W6ZRN/6 teurs' Club has been hard at work on plans for l.86 Miles-July 27, 1947 the forthcoming National ARRL Convention 1215 Mc.: W3MLN/3 - W3HF'W /3 to be held in Milwaukee, Wisconsin, Sept. 4th, 12.5 Miles - Septemher 2,t, 19-17 5th and 6th. This would appear to. be the right 2300 Mc.: Wl.lSM/1- WllLS/1 spot for the nationwide v.h.f. get-together, ide!U:! 66 Miles - October 5, 1947 for which have been bormcing around for some 3300 Mc.: W6IFE/6-W6ET/6 1.50 Miles - October 5, 1947 time. Every effort is being 1.nade by the Conven 5250 Mc.: W2LGF/2-W7FQF/2 tion Committee to provide adequate facilities for 31 Miles - December 2, 1945 the v.h.f. fraternity. A special V.ILF. Committee 10,000 Mc.: W4IIPJ/3-W6IFE/3 under the chairmanship of Frank Maiorana, 7.65 Miles-July 11, 1946 W9TPT, is arranging an extensive program of · 21,000 Mc.: WlNVL/2 - W9SAD/2 v.h.f. activities, and a total of eleven hours of 800 Feet - May 18, 1946 convention program time is set aside specifically for this purpose. There will be hidden-transmitter hunts and path appeared to be dropping off in late April, other outdoor activities, including a competition and it is probable that the last opportunity for a for the best mobile installation. Fine prizes will CE-ZS 50-Mc. QSO has passed for this season. be available for these, as well as for other com In all the years since the first v.h.f. DX was petitions, the object of which is to encourage the heard, we've had some strange doings reported amateur v.h.f. experimenter to show his wares on the v.h.f. bands. Here is one such: On March at the convention. V.h.f. exciters, converters and 27th VE5CO, Moosejaw, Saskatchewan, heard microwave trallSmitters will be the subject of VS5Y on about 54 Mc. Heard first around noon individual competitiollS. PersollS desiring to enter (MST) the signal was in again around 1 :27. The these judging competitiollS are requested to get operator had a pronounced English accent and in touch with Jack Doyle, W9GPI, general delivery, and appeared to be testing with another eonvention chairman, 4331 N. Wildwood Ave., station. Can anyone furnish more details? Milwaukee 11, Wis. The spring of 1948 has been conspicuous for at A period of four hours is being allotted to a least one thing: the lack of aurora DX on 50 v.h.f. get-together Saturday night. Sunday morn Mc. The period from .February through April ing will feature transmitter hunts, demollStra usually provides several openings of this nature, tions of u.h.f. and microwave gear, and the but even the 10-meter band has seen very little vaiious judging competitiollS. More v.h.f. talks sign of it this year. Between 7:07 and 7:15 P.M. and meetings are scheduled for Monday morning, CST on April 7th W9NJT, Watertown, Wis., ending in awarding of the v.h.f. prizes. heard WlAW and one unidentified commercial Many notables in the v.h.f. field are expected signal (where was everybody else?) and again on to be present, and the time available should make t,he 13th he worked W9PK and heard W9ALU it possible to hear from everyone. Here, at last, and W9EVL. is a convention where the v.h.f. man can feel at There was a bright aurora in New England just home. He will have ample opportunity to meet before midnight April 21st, but it came too late to with others whose interests follow the same chan find 1.nany of the gang in the East still active. nels, instead of having a few minutes sandwiched Those t,wo reliables, W2AMJ and W2BYM, in at some inconvenient time in the program. So worked some W8s, but otherwise little has been lct.'s make it a date - see you in Milwaukee! reported on 6. W3RUE, Pittsburgh, Penna., was on the job, however, and fill he has done whenever Helpful Hints Department aurora signals have been heard on 6, he checked Ever try to get a radiation pattern of your the 2-meter band to see if anything peculiar was 420-Mc. array? If you have, you know that re in evidence. Long ago he'd decided that the aurora flections from surrounding objects can be mighty had no effect on 2-meter propagation, but this confusing. A person walking several wavelengths night he heard a signal on 144.2 Mc. which had in back of the field-strength meter, for instance, all the earmarks of aurora reflection. Swinging the will cause readings to vary widely. To get around beam to the north brought the signal up mark this difficulty, W3GKP, Silver Spring, Maryland, edly, but the voice was unreadable because of the uses one of the CS-48 storage cru,es from the 48 QST for tuning units of the BC-375 transmitter as a slot for 420 Mc. and higher. He suggests that some or cavity antenna for his fielcl-strength meter. reader put him in touch with a reputable grave To eheck the idea a similar unit was built in the robber, who would dig him up a 144-Mc. job! Headquarters lab, and a photograph is reproduced herewith. As may be seen, a rn.icroammeter iR A B.F.O. for the 522 Receiver mounted at, the center of the box opening, in With the increased use of c.w. on 144 Mc., the series with a crystal diode and two ::ihort lengths users of 522 receivers are at some disadvantage of tubing. Copper tubing :!-:{ 6 inch in diameter in having no beat rnwillators. And even if the was used, as this can be readily tapped with a 6-!'l2 thread._ One section of tubing has a loop of No. 1G 2.omh. wire soldered to it to form a lug fitting over the 0000.oKc. .----r-d/0 Xtal meter terminal The other piece is soldered to a 1N34 diode, the other end of which connects to the other meter terminal. The two µieee.,; are just so long enough to fit inside the box and are fastened ppfd. in place with short fi-:32 screws through the sides of the box. -- Polarization is parallel to t,he wire; that is, with the unit in the position shown, polarization Schematic diagram of the Pierce oscillator used as a b.f.o. in a 522 receiver by Wf!CCY. Values are not criti is horizontal. The main lobe is in front of the cal, and no injection coupling is required. open side of the box. The arrangement has a useful gain over a dipole, in addition to greatly operator is one of those who is allergic to c.w. reducing trouble experienced from reflections. as a mode of communication, the b.f.o. is still The only disadvantage Smitty can think of is a mighty handy article in combing the hand that, with the box having a cut-off frequency for the weaker sigs. W000Y, Council Bluffs, of about 300 to 350 Mc., the gadget is good only Iowa, uses the crystal-controlled b.f.o . .,;hown in Fig. 1. The complete story is on the diagram, and values are not, erit.ieal. No injection coupling was needed in his ease, the ,;eeond harmonic being strong enough for b.f.o. purposes with no more coupling than that afforded hy the r1\~eivcr wiring. Here and There Houston, Texas ----The 144-Mc. DX season starts early along the Gulf Coast. As early as March 23rd five stations in Corpus Christi came through in Houston with good signals, aecording to W5FSC. W5SM in Beaumont heard a station in Harlingen, a distance of about 350 miles. Kingsville, about 150 miles to the south, is the bP,st DX worked on 144 Mc. from Houston so far. W5SM, Beaumont_, and W5DAA, Kingsville, hold the two-way record for the Gulf Coast, about 290 miles. 'The Houston area should have good representation on 50 Mc. this year, as W5s IGL, KFY, MRV, FSO, EEX, BHO, ADZ, and UW are all set, for business. Sea Oirt, N. J. ----- Having a horizontal 144-Me. array paid dividends for W200C on the night ot' April 4th. Hearing stations coming through un usually well on his vertical, W200C swung hil:! newly-erected horizontal around to t,he south. Out dropped the qRM from the near-by vertical locals and there was W4CLY, Cape Henry, Va., rolling in S8. Between 11 :30 P.M. and 12:30 A.M. contacts were made with W4IKZ, near Norfolk, A field-strength indicator for 420 Mc. made from the W4CLY rui.d W4JFU, Parksley, Va., all hori case of a BC-375 tuning unit, a microammeter, a 1N34 wntally-polarized. The distance is in excess of crystal, and two pieces of copper tubing. This model was 250 miles. assembled in the Headquarters lab at the suggestion of W3GKP, who uses a similar arrangement to eliminate W 4FJ, Richmond, Ya., reports loud signals reflections from objects in hack of the meter. from horizontally-polarized W3KCA, Baltimore, June 1948 49 stations in the Greater New York area constitute the main reason behind the decision of the V.H.F. Institute of New York to remain vertically polarized. Many of the stations in heavily populated areas are not able to put up rotatable arrays, and, where a simple fixed antenna must ~~ /~' be used, results are bound to be better with _,,· -..____, ve!.'tical polarization. 'fhe large numbers of Standings as of April 30th mobile stations, and the presence of television WlCLS 44 W5VY 40 W9ZHL 43 and f.m. receivers using horizontal antennas, W3CIR/I 4 .. , W5ML 38 W9JMS 36 are two more reasons for their. continuing with WlLLL 40 W5AJG 38 W9ALU 34 vertical polarization. WIHDQ 39 W5.TLY 38 W9QKM 33 WICGY 38 W5FRD 38 W9UIA 31 Louisville, Ky. -An emergency net is operat WlHMS 36 W5ZZF 34 W9AB 23 ing in the Louisville area on 145.8 Mc. Persons WlJLK 35 W5FSC 34 interested in participating are requested to get WINF 35 W5LIU 24 W0USI 45 WlLSN :33 W0QIN 43 in touch with W4BPE or W4FBJ. WlCLH cl2 W8UXN 48 WJ!ZJB .4:1 Atlanta, Oa. --The Atlanta-area emergency \VlCJL 30 W60VK 38 W0DZM 42 net operates on 144.138 Mc. each Monday at WlAF W6ANN 27 38 W0TQK 42 8:30 P,M. At 9 P.M. they stand by for contacts W!EIO 24 W6BPT 34 w0sv 42 W!HIL 21 W6IWS 32 W0B,JF 42 outside the area, and schedules for this period W6l!'PV 31 W0HXY 41 are solicited. W4LNG and W4KHL made a W2BYM 39 W6WNN 2-1 W0INI 41 trip to Westminster, South Carolina, on March W2AMJ 38 W6EUL 22 W0YUQ 39 W2IDZ :l7 W6HZ 13 W0JHS 38 27th and worked W4LMF of Atlanta and heard W2QVH 37 W6BWG 12 W0PKD 36 W4KIP. The following day they journeyed to W2RLV 37 Bald Mountain, near Franklin, North Carolina, W7BQX 43 VElQY 28 where the same two stations were heard with W30R 35 W7ERA 43 VE3ANY 27 WlKMZ/3 33 W7HEA 40 VEIQZ 24 good strength. Trouble developed in the portable W3MKL 33 W7DYD 37 G5BY 24 rig, however, so no contacts were made. W3RUE 32 W7FDJ 36 VE2KH 19 Medford, Maas. - WlKNI reports that W3MQU 15 W7FFE 35 YE2GT l4 W3GKP 12 W7KAD 35 XB!KE Ja WlBZN is trying out circular polarization on W7JPA 34 420 Mc. Rotating the 16-element array at W4GJO 48 W7QAP 30 WlKNI from vertical to horizontal produces a W4QN 40 W7ACD 27 ehange of less than ten per cent in signal level at W4GIY 40 W7JPN 19 W4EQM 40 W70WX 15 WlBZN when the circularly-polarized antenna W4EID 38 is used for receiving. WlKNI has been trying W4WMI 33 WSQYD 39 some i.f.-strip modifications in his APS-13. W4FBH 31 W8RFW 25 W4HVV 29 WSTDJ 22 Removing the loading resistors sharpened the W4FJ 26 i.f. too much for the unstable signals on the band. W4FNR 2,5 W9DWU 48 A try for a.v.c. was not too successful, as the W4EMM 25 W9PK 43 6AG5 is not well suited to this sort of operation. W4JML !JO Tue13on, Ariz. -The 50-Mc. group in this Note: This list covers states worked since March area now comprises W7s OWX, UPF, UPR and 1, 1946. Send in monthly reports of states worked in QAP. No DX was heard up to the latter part of 1948 on 50. 144, 220 Mc. and higher, for entry in April, but W7QAP reports that he will be on the the 1948 Most-States-Worked Contest. See January QS'l', page 150, for details. Standings will be pub- band regularly between 5 and 10 P.M. MST, lished when sufficient entries have been received. watching for openings. Bud is also on 144 Mc. and would like some early-morning schedules with stations in the vicinity of Phoenix. and W3ENZ, W ash.ington, this same evening. San Bernardino, Calif. - Activity on 144 Mc. W3DOG, Laurel, Delaware, was strong despite is growing by leaps and bounds according to his vertical array, and his contact with W4IKZ W6UAH, who lists 19 stations as most active: rates as the season's cross-polarization DX. W6s CON, DMQ, HCX, HKD, JZT, KBG, South Plainfield, N. J. - How many stations TG{G, QUK, RSN, RUT, RSR, RXA, SJB, can be worked on 144 Mc.? W2NLY is well past UAH, UXG, VSF, WTT, YAB and W0HIIN /6. his first thousand and still going strong! Jim Contact is made with stations in the Los Angeles makes a plea for more use of c.w. on 144 Mc. area, some 60 to 80 miles to the west, by pointing In the midst of the welter of activity in that directional arrays at Mt. San Bernardino, due metropolitan area weak DX signals are much east. Direct-line contacts are extremely poor. more readily identified on c.w. than on 'phone. W6QUK has worked San Diego, more than 100 Weak carriers are often heard in the direction of miles distant, over very high mountains. Lan W4 which would be solidly readable on c.w. caster, about 40 miles out in the desert, with M.aspeth, N. Y. -The more than a thousand ((Jontinued on page 111!) so OST for HAMFEST CALENDAR A.R.R.L. QSL BUREAU. ALABAMA - The Annual Field Day & Hamfcst of the OR the convenience of American and Canadian Anniston Radio Club will be held on Sunday, June 13th, on Cheaha Mountain, 20 milea south of Anniston. Good food, Famateurs, the League maintains a QSL-card games, competitions and rag-chewing will be tbe fun of the distributing system which operates through vol day. Bring the family! Tickets are available from W. L. unteer district QSL managers in each call area. Robinson, W4GYD, 415 Goodwin Circle, Anniston, Ala To secure ·such foreign cards as may be received bama. ILLINOIS - All road• will lead to Camp Ki-Shau-Wau for you, send your district manager a stationer's - near Starved Rock State Park - on Sunday, June 6th, size No. 10 stamped self-addressed envelope. If when the Starved Rock Radio Club holds its big Hamfest. you have reason to expect a considerable number Follow the signs south from the junction of Illinois Routes 71 and 178. Entertainment, speakers, exhibits, contests aud of cards, put on an extra stamp so that it has a refreshments are programmed, starting at 10:00 A.M., total of six cents postage. Your own name and rain or shine. Lunch will be available at the camp. Registra- address go in the customary place on the face, and 1,ion $1.00. ILLINOIS - June 27th is this year's date for the Annual your station call should be printed prominently Picnic of the lllinois Central Radio Amateur Association, in the upper left-hand corner. If you have held which is composed of the Twin City, Cenois, and Kickapoo other calls in previous years, submit an envelope Radio Operators clubs. The get-together will be held in the for each such call to the proper manager - there amphitheater overlooking the lake at Weldon Springs Park, near Clinton. There is no registration charge, and hams and are many thousands of uncalled-for cards in the their friends are invited. Bring your own lunch - the asso files. All incoming cards are routed by Hq. ciation. will furnish free soft drinks. Further particulars may to the horne (/,istrict of the call shown in the ad be obtained from Ed Harney, W9PEK, 521 N. Quincy Street, Clinton, lll. dress. Therefore, cards for portable operation in MlNNESOTA - A bang-up program has been arranged other districts should be obtained from the home for the first postwar Gopher Hamfeat, to be held Friday and district manager. Saturday, June 18th-19th, under t,he auspices of the Minneapolis and St. Paul Radio Clubs. The affair, to be Wl, Kl - Charles Mellen, WlFH, 320 Cornell St., Boston, Mass. held at the Hotel Nicollet, Minneapolis, will feature tech nical ta1ks, conteste: turkey dinner and entertainment. W2, K2- HenryW. Yahne!, W2SN, Lake Ave., Helmetta, 1 N. Reservations made by June 14th, $5.00; at hamfest, $5.50. J. Ladies Free room11 are available the homes of local W3, K3 -- Jesse Bieberman, W3KT, Box 34, Philadelphia, $3.50. at Pa. amateurs for advance registrants if requeated. For tickets and information write Gopher Hamfeat, Box 685, Minneapo W 4, K4 - Johnny Dortch, W 4DDF, 1611 .Flast Cahal Ave .. Nashville, Tenn. lis, Minnesota. W5, K5 - L. W. May, jr., W5AJG, 9428 Hobart St., VERMONT - The Burlington Amateur Radio Club is Dallas 18, Texas. aponsoring the Northern Region Ham.fest on Saturday, W6, K6 - Horace R. Greer, W6TI, 414 Fairmount Ave., ,July 8rd, at the Heineberg Community Club, Burlington. Oakland, Calif. A lively program has been planned, including a 2-meter W7, K7 - Frank E. Pratt, W7DXZ, 5023 i:i. Ferry St., treasure hunt, ARRL Club Award code contest, technical Tacoma, Wash. speakers. Emergency Corps meeting, eats and dancing. W8, KS-Fred W. Allen, W8GER, 1959 Riverside Drive, Registration: UMs $3.00, XYLs and YLs 75~. Burt Dean, Dayton 5, Ohio. WlNLO, Box 81, Burlington, Vt., be glad to P.O. will W9, K9-,John F. Schneider, W9CFT, 311 W. Ross Ave .. supply further information. · · ' Wausau, Wis. Wll, Kl! - Alva A. Smith, W0DMA, 238 East !\Iain St., Caledonia, Minn. VEl -- L. J. Fader, VElFQ, 125 Henry St., Halifax, N. S. ii,ilent Jkeps VE2 - Austin A. W. Smith, '.\'E2UW, 6164 Jeanne Mance, Montreal 8, Que. T rs with deep regret that we record the VE3 -- W. Bert Knowles, VE3QB, Lanark, Ont. Ipassing of these amateurs: VE4 - Len Cuff, VE4LC, 286 Rutland St., St. James. Manitoba. WlFX, H. R. McLane, Laconia, N. H._ VE5- Fred Ward, VE50P, 899 Connaught Ave., Moose W20VQ, Lawrence B. Wollins, Yonkers, ,Jaw, Sask. VE6- W. R. Savage, VE6EO, 329 15th St. North, Leth N.Y. bridge, Al ta. W4FXL, Thomas M. Mason, Meri , VE7 - H. R. Hough, VE7HR, 1785 Emerson St., Victoria, weather, S. C. B.C. W4GIC, Wendell L. Longstreth, Braden- VE8 - Yukon A. R. C , P. O. Box 268, Whitehorse, Y. T. KP4 - E. W. Mayer, KP4KD, P. 0. Box 1061, San Juan, t,on Beach, Fla. , P.R. W4PK, George W. Clark, jr., Jackson KZ5 - C.Z.A.R.A., Box 407, Balboa, Canal Zone. ville, Fla. KH6 - Andy II. Fuchikami, KH6BA, 2543 Namauu Dr., Honolulu, T. II. W5ASJ, Stewart E. Atwood, Shreveport, KL7 - J. W. McKinley, KL7CK, Box 1533, Juneau, La. Alaska. W6VIY, Eugene S. Brown, Long Beach, Calif. ~Stray~ WSHDU, Harold E. Forest, Toledo, Ohio W9SKA, William E. Flood, River Forest, For the benefit of the ham who lost his grid Ill. drive the other night, W0QVA calls attention to G3NI, Frank ;rackson, Camsborough, the following ad from the Burlington (Iowa) Yorkshire Hawk-Eye Gazette: MILLIAMPERES found. Owner identify and pay for ad. Call at Want Ad department. June 1948 61 Tripling to 420 A Simple Frequency Multipliez· To Pz-ovide Useful Output on 420 Mc. BY JAMES W. BRANNIN,* W60VK ER playing around a hit with self-excited oscillators in the 420-Mc. band and ex • The modulated oscillator has heen the K periencing the usual pul~g, downward generally-accepted means of getting modulation, and other troubles which_ are charac ~tarted on 420 Me., and it probably will teristic of modulated oscillators on this and other remain so for some time, hut the genera bands, it was decided that some sort of frequency tion of useful amounts of stable energy at 420 Mc. is not necessarily difficult. Here controlled transmitter would be the only really W60VK describes a tripler that can be satisfactory way to operate in this territory. A used in conjunction with a 2-meter crys likely tube or pair of tubes which would perform tal rig to provide several watts of power as a tripler or amplifier at these frequencies ap in our lowest u.h.f. band. peared to be too much for the old pocketbook, so the project was confined to wishful thinking until Milt Cooper, W6QT, passed along the informa quency in the 144-Mc. band is suit~ble_ f~r tion that he was doing a pretty good job with an tripling purposes. The tripler plate ctrcmt 1s SCR-522, operating in the 420-Mc. band with simply a "U"-shapcd loop, which is tuned by no changes in the tube line-up! means of a small copper disk mounted just above Thanks to this suggestion, we arc now pushing it. A 60-ma. pilot lamp coupled loosely to the several watts of crystal-controlled power into the plate circuit serves.as the best indication of reso antenna coaxial line, putting an 89 signal into nance, there being almost no dip in_ plate current Bm·keley, some 30 miles across the bay; yet the as the tank circuit is tuned for maximum output. pocketbook is hardly the worse off for it. . Nothing difficult or tricky is involved in at Physical Layout taining this end, the principal clement of novelty The chassis was made by mounting a 5 X 5- being ·the arrangement of the tripler plate-tank inch piece of sheet copper in an upright posit!on circuit. The 882-A is driven harder and biaserl. on an old switch-box lid, the sheet copper bemg higher than would be considered necessary for held in place hy two metal angle b:ackets. The operation at a lower frequency. A minimum of tube is mounted horizontally for obvious reasons. 10 watts should be available for this purpose, A piece of ¾-inch polystyrene is used as a sup and the driver may well be a 522 or similar rig port for the tuning disk, although any other ma normally used for 144-Mc. operation. Any fre- terial could be substituted. The means of mount * 225 Park St., Redwood City, Calif. ing the disk and support are clear from the ~ accompanying photograph. The tube socket is the type that provides shielding and by-passing of the screen and filament terminals as an integral part of the socket, and is to be preferred for high frequency use. The grid coil and tuning condenser are mounted on stand-offs attached to the base of the socket. The two-turn grid link iR attached to terminals mounted in a small block of polystyrene at the back of the chassis. The plate line is made of \½'5- • The 832-A tripler described hy W60VK. • 82 OST for tained, the loop may be removed and the grid About tbe Autbor ,,ircuit tuned for maximum output from the plate circuit, as indicated in the lamp coupled to the • James W. Brannin, W60VK, needs no platt) line., introduction to readers whose.main in~ Some adjustment of the position of t.he plate tcrcst in amateur radio lies in the fre quencies above 50 Mc. He was first line on the tube pins may be necessary to estab licensed in 1920 as 50K, and has also lish resonance in the plate circuit, as there is an held W2BYE and W5DCI, as wf'Jl as his appreciable variation in the output capacitance present <'all. He is one of those old a,nd lead length of various 832-A tubes. It may timers who has gone through the DX even be necessary to change the length of the and traffic phases of hamming and now "U" a small amount one way or the other. The finds his main enjoyment in v.h.f. ex length of the loop, or its po.sition on the plate perimental work, his record on 6, 5, pins, should be adjusted so that the circuit reso 2½, 2, and I¼ meters establishing him as one of the leaders in this field. nates with the tuning disk at the approximate position shown in the photograph. As attach ment of the antenna and adjustment of the posi tion of the output coupling loop affect the setting inch copper tubing bent into a "U," the sides of PLATE TANK which are 1½ inches long and l;½'.6 inch be tween centers, at which spacing they just slide over the 832-A plate pins. The ends are tapped for 4-36 screws which serve to hold the line ---\7 / firmly on the plate terminals. The top of the Copper ___ _.,,.,,.. 13 11 i·{ lo upright bracket, on which the coaxial antenna Tubing connector is mounted, is even with the level of the plate line and is used as the ground point of ___ the by-pass condenser, Ca. Plate voltage is fed ~------[ ~ into the middle of the "U" through a small ,_._-----Ir------< r.f. choke. Above the line is the loop for the indi I cator lamp, and below it is the coupling loop Fig. 2 -·- Detail drawing of the 832-A plate line. which is connected to the coaxial output fitting. of the tuning disk considerably, it is advisable to Tuning & Operation readjust it carefully once the antenna has been For best results the tupe must be driven fairly connected. Some sort of field-strength meter is hard, a minimum of lO watts being desirable. almost a necessity in this procedure. Tuning of the grid circuit may be accomplished Initial adjustments should be made with low by means of a 60-ma. lamp coupled to the grid plate and screen voltages to prevent damage to coil. After an approximate setting has hcen ob- the tube. About 200 volts on the plate and 150 on the screen will do. This precaution may save an 832, and several 60-ma. pilot lamps as well. After the circuits are properly adjusted the plate voltage may be increased to 300 and the screen voltage to 220. Plate current, under these conditions, will be about 60 ma. The coupling to the output indicator lamp should he reduced before the volt,age is raised. This coupling should he just sufficient to produce a visible indication for tuning purposes. With an input of 18 to 22 watts the measured output was about 6 watts, and upward modula +300 tion was obtained on the first trial. It is felt that this tripler offers an easy way for anyone now Fig. I - Schematic diagram of the ·1,20-Mc. tripler. C, -25-µµfd. midget variable. having a crystal-controlled rig on 144 Mc. to get C2 - Screen by-pass, built into socket. Use 100 µµfd. on 420 as well. Its coRt and complexity are com if external. parable to a modulated oseillator of the ~ame Cs - lO0-µµfd. mica. power capability, yet the results obtained are R1 - 0.4 megohm, 2 watts. R2 - 2!>,000 ohms. 10 watts. far more satisfactory. L1 - 2 turns No. 18 insulated, tightly coupled to L2. L2 - 3 tnrns No. 14, ½-inch diameter, ,Hi inch long. La - Plate line; see sketch. ' L, -- Hairpin loop; see photograph. SWITCH l 1 - 60-ma, pilot lamp, with hairpin loop. RFC, - 50 tnrns No. 28 d.s.c. ou ¼-inch rod. RFC2, RFCa- 5 turns No. 20, ~io-inch diameter, }~ TO SAFETY! inch long. June 1948 53 Revised WWV Schedule Preview of ~TANDARD-FREQUENCY transmissions are made S continuously, day and night, as a public DX Contest 'Phone Scores service by the National Bureau of Standards over HE rE>..ason for that strange gargling noise its standard-frequency station, WWV, on t,he T we've been hearing on the 'phone bands the following frequencies: past few months can now be revealed -···• the Pow,r Audio Fr,q. 'phone session of the 14th ARRL DX Competi Mc. (kw.) (cycles) tion was to blame. And with the gaudy assortment 2.5 0.7 1 and 440 of DX that showed up on both week-ends, no 5.0 8.0 1 and 440 10.0 ll.O 1, 440 and 4000 small wonder! 15.0 9.0 I, 440 and 4000 We have gathered together a list of the highest 20.0 8.5 1, 440 and 4000 available scores, which will give you an idea of :!5.0 0.1 1, 440 and 4000 the new peak in activity reached in this annual ao.o 0.1 1 and 440 ;15.0 0.1 1 feature. Several of the stations who were really knocking them off have not as yet been heard A 0.005-second pulse may be heard as a faint from, so this early report, is by no means complete. tfok every second, except the 59th second of each Remember, too, there still remains the prodigious minute. These pulses may be used for accurate task of cross-checking all logs before scores can time signals, and their one-second spacing pro be announced as official. vides an accurate time interval for physical On top of the pile we again find W2SAI, last measurements. year's 'phone winner. John has really proved bis The audio frequencies are interrupted at pre championship mettle this time, his log showing a cisely one minute before each hour and each five total of 265,392 points, representing 582 contacts minutes thereafter (59th minute; 4 minutes past with stations in 84 different countries. hour, 9 minutes past hour, etc.), resuming after For second, W2AFQ and W3BES are very an interval of precisely one minute. This one close to a dead heat in claimed voice scores - minute interval is provided to give Eastern 141,840 and 141,642 respectively. Another Standard Time in telegraphic code and to afford wheeze by Mr. Mathis might have given him the an interval for the checking of radio-frequency nod. Four other score,S over the hundred thousand measurements free from the presence of the audio mark also are available, these being the out frequencies. Ionospheric-disturbance warnings standing performances of W8KML, 135,509, applicable to the North Atlantic path are given W3NJE, 122,086, W3DHM, 118,560, WSBKP, at 19 and 49 minutes past each hour. If a diB 101,760. turbance is in progress or is anticipated within 12 The roster of other claimed scores over 40,000 hours, the time announcement is followed by 6 includes: W2RGV 97,440, WSHUD 92,567, Ws; if conditions arc quiet or normal, the time W9HEI 86,040, W8REU 82,251, W2BXA 80,- announcement is followed by 8 Ns. The announce 840, WlJCX 83,325, W2ATE 75,272, W6TT ments of the station's services and of the station's 71,010, W3NC 68,252, W4DQH 64,347, W4LAY eall (WWV) are given by voice at the hour and 60,861, WlCJH 60,378, W6EJC 57,285, WlBFB half hour. 56,072, W2RYT 55,675, WlME 54,315, W9EWC The accuracy of all the frequencies; radio and 52,208, W6AED 50,589, W6MLY 47,424, audio, as transmitted, is now better than a part W7ESK 46,992, W4EWY 46,170, WlKLE . in 50,000,000. Transmission effects in the medium 44,625, W5BGP 43,845, W2AQW 43,677, may result in slight fluctuations in the audio W3FGB 43,092; W3FUV 42,408, W7HTB 41,- frequencies as received at a particular place; the 535, W6IDY 41,184. average frequency received, however, is as accu You'll note that many of these exponents of rate as that transmitted. The time interval the spoken word also ·knocked themselves out in marked by the pulse every second is accurate to the c.w. fracas. ]for instance, W2BXA's impres 0.000001 second. The beginnings of the periods sive 'phone score was accompanied by a e.w. when the audio frequencies are resumed are tally of 212,160 points, which was omitted in last synchronized with the basic time service of the month's radiotelegraph synopsis. U. S. Naval Observatory. Reports from the overseas mob are lacking but we do have a pair of high Canadian boys, VE3HC with 68,816 points and VElET with 40,824 points. You'd think that one of these brawls would be SWITCH enough for the average person, but a listen over the bands right now will bring you that familiar TO SAFETY! phrase, oft repeated, " but wait 'til next year!" 64 QST for 0 ~-~-r•·· l?(1\J Hows DX? ,_ CONDUCTED BY ROD NEWKIRK,* W9BRD/l absolutely no eonsi June 1948 66 . _. _. _ Still convalescing from an operation VEIEA operated on MD5KW, UT3.AB, PAJlOK, ON4JW, ON4QF, OKIMB, IIB9DD, HB9FF, SM5BO, SM5FU, GW3ZV plus some Fs and G::1 .. . . . _ A sturdy 815 at W3VZD snagged <>N4AF, ON4HO, OKlLM, OKlMG, HB9.AJ, F3MS, V06R and ZS6DW. _. _ .. While his rig was t,orn down, W0UXQ tortured hin:Jself b.v hearing VR5PL, FMSAD, VK2RA, VK2CX, and sundry other rarities . _ . _ . _ Who has more than W4BRB's 45 3.5-Mc. countries'? Porty: Not quite ready for its summer slump, 7 Mc. still is evoking many delightful cries of joy. Giggling fiendishly, \V9VES came uut with KP6AA, LU5BM, VP9E, HP4Q, PY2A.FS, VP7NG, EL3A, ZSlM and VR5IP .... _. _ Thirty-;;ix countries in just two weeks kept WSKPL busy. These included: VPSMU (7080), CM6ZK, KV4AA, PY7WS, SM5BX, FM8AD (7020), HB9AW (7030), HB9U (7050), IlMQ, UAIV, VK3AEP, VK5JE, CI2HML and J3AAD (7040) for WAC on this band._._._ ::-itill short of Asia, W8YGR produced QSOs with KP4HE (7007), FA8BG (7010), V03Z (7023), SM4AGB (7009) and VE8NQ (7071). _. _. _ KH6PT blew up his power supply and was so disgusted he hooked a 90-volt B battery to a 184 crystal oscillator to ;;ee if he could scare up an other KII6 local to tell his troubles to -· but W6ZMU was there to answer his 1.62-watt CQ. W6ZMU had only 35 watts, so it looks as if the ,lays of QRP aren't over yet! Tu-enty: We again come to the band as far The eqwpment shown here has been a harbinger of as DX iR concerned. 'Nough said. A note from joy to many a DX hunter for the past year or so - W60BD Htarts us off on the right foot with uperated under the call KS4AI on Swan Island by HElEO (14,130), FT4AN (14,000), CR6AQ ]{alph W. Bird, W5KWY. A long-wire antenna pro vided excellent all-hand results with the 100-watt trans (14,055), VP6PX (14,035), VS4WL (14,040), mitter. Line-up: 6V6-807-push-pull 80Qs. KS4Al is now FE8AB (14,125), GDZDF (14,105), XZZEM () RT so all correspomlence to Ralph should go to his (14,025), XZZJB (14,140), UAlKEC (14,130), home ()TH. UC2CB, UBSDD (14,120), UH8KAA (14,070), UA9CC (14,180) and VQ3HJP. Lee has evidently What: worked· them too fast to keep up his average, Eiyhtu: That ole debbil QRN is back, pinning which is 05 veried out of 121 . _. _._A neat the ears of the 3.5-Mc. gentry, after lying dor 'phone trick at W3UY was YilB (14,312) mant for many months. The pride of Plaquemine, . _ . __ . _ W7BE can sit back and relax (as if he W5KC, nicked the band for a nice \YAO, despite will!) since he i'l now in for both DXCC and t.he ri,;ing static: .JaAAD, HClJB, FA.SBC, WAZ. His latest: C8YR (14,050). _._._The. KL7LE, HB9A W and ZLlMB. Vince is up to 809s and 3-element spinner at W6LRU clicked 157 worked now with 25 countries on 80 .... _ . _ with UCZAD (14,050), URZKAA (14,025), In Montana, W7KVU also did the hat trick with UNlAA (14,104), EAlA (14,130), VUZBX his 150-watter on UA0KAA, CE3AG, G2.TT, (14,012), CN8BK (14,000), XZ2KN (14,085), ZLIDI, ZS3D and VP7NG . _. - . _ W9AND MI6ZJ (14,029), YVlAZ (14,095), HP4Q (14,- needs Asia but accounted for KZ5FS, KZ50J, 050), VRSPL (14,012), WfJOZW /KS6 (14,029) KZ5AX, XEIKE, CM2SW, KS4AI, 1IB6LF, for 101 postwar._._._ On voice, W3QLW W60RT/KH6 and Tl2KP . _._._School keeps conversed with CTlIP, D4ABA, D4AQW, interfering with W4KVM's DX-factory business HH3DL, OX3BE, OX3GE, V04Q, VP2GE, but ,Tim managed ZLlDI, F9KH, FSEO, VP3LF, VP9Q and YV6AN. _ .... _ WSWWU OKIEA, FASBG, TG9JK, ON4HC, LAIS, did well with VS9AN (14,025), HLlAE (14,045), XFIA, GW5TW and some Gs._. __ . __ 'W4CVM. XSVlKE (14,025) and CTlDK (14,012) despite who probably gets tangled up with W4KVM heavy whooping-cough QRM from the junior ops at times, donates KII6NE, ZL2FA, FA8IH, . _ . _ . _ W3LPF made it 100 even with GC2ASO XEliill, PA0RE, KV4AA, ON4AU and G5TA but glooms about no QSLs from Latin American 56 OST for countries . _ . _._At W8ZBK we have .APSB FE8AB, CX4CZ and an FA8. _. _. _ W2KZE (14,045), VK6JB (14,100), LUlXK (14,160), tired of working (}13, so he QSOd HB9FY, VP4TZ (14,120), VK7KN (14,100) and EAID UA3BJ, ZLlLZ; PA~IN, OZ7ON, LU5BM and (14,075). _._•.-Transplanting himself from SM5UU . _ .... _ From the heart of Alabammy, W3BUI to W2BUI necessitated starting all over W4GLR ships us a huge list of successful snaffles. again. Hal's first month produced 61 countries We choose a few: KH6KW, VQ3HGE, J2RLK, worked and 2 nonfirmed! . _ . _ . _ W 4L WP's J2SJS, J2HYS, ,J2ACS, MD5GW, KG6ON, 25-watt 807 didn't shy away from CMlAU, PZlD, OMAN, GD6IA, ZD4AH, OH2QM, KM6AA, CR6AI, CTlPP, VP5AK, HH3L, VO6AD, GO2RS, XARC, VP5AS, HLlAN, PK6SA, CE3BA, TI2BF, VP2AA, ZSlEJ, l:IPlA, ZClAF, CTIQA, CE7AF, ZBlS, LXlAI, ZS6LW, OA4BR and a truckload of VKs in OX3GE, HZlAB, · VQ2DH and KG6A W /VK9. cluding 9OU, 9RF and W~TKK/VK9. P.S.; The Wow! 807 wa.'< doubling! . _. _ . _ W6ZCY kept one eye Elwen: Did you ever notire that on some davs open and made off with VS9ET, CT3AB, t,his band is open while ten, just a megacy;le ZC6NJ, CR6AQ, YSlV, YU7AF, CZ2AO and higher, is almost stone-dead'? One of the more C8YR . _. _. _ OZ2AO was also snapped up by observant gentlemen, W9AND, has accumulated W5ASG, besides YU7KX, YU7LX, UAPFG, stuff on the order of EL5A, OX3GE, VO4T, f:fiYZ and KM6AH. Then modulation did its KH6GT, KII6BI and CXlFB. Wes needs onlv stuff for Bill on W6YOT /06, MD5PS, ST2FU, Asia for a 27-Mc. WAC and W6ZZ reports work MI3ZJ, SVlRX, SVlWE, OH2QM, GC2RS, ing J9AAI. Who el;se has anything to say about .El'3AF, HA4AB, VR2AP and EAlFO . _. _. _ this 270-kc. i-;tretch of DX potentiality? Ah, we finally come to a W9 who is working Where: something. Namely, W9LNH, with VP5JT., \TPlAA, VP9F, EKlAA, UISAA, EL5A, ZB2A New c:atche::; are still getting on the air as at and CTlQF, the latter three on 'phone . _ . _ . _ tested to by the follo~ing list: "I could have done better with a beam," com CPIJI % American Embassy, La Paz, Bolivia CR6AR Box 147, Benguela, Angola ments W5GEL after slaving for CR9AG, CNSMZ, CZ2AC N'icolo Teatro Ristori, 704 Malmedy Vil- GA~KFA, CR7V-\L, YSlBA, W~MCF /01, lag;e. 1\1onaco W2WMV /09 and VS2AL, plus umpteen more. Not much better, we should think!._._._ W3EVW conglomerated a nice 70-minute.WAC with a YU7, ZS6QX, PY2AT, ZC6AO, VK5FL tmd' VO6X. A kw. really pays off these days . -·· .... _ OH2SJ /MM was hooked by WlMRQ while near C:i,diz, Spain. Naturally, Ken needs EA badly. 80 near and yet so far! But WlMRQ got, landlubbers CM9AB, an EK, HK3FF, ZD8B, OKlZM, OZ9NH, PYlDS, ZS2EK, ZS6CZ and GI6WG. Ten: ScTam, Tilton. Goodman got here first. But evidently WlGOU wasn't far behind with EA7BA, VR6AA, CR7AD, PK2RK, ARSAB, ZOlAF, FF3JY, ST2FU, VU2GB, VQ4ASC, V(~4ERR and \TK7A,T. These were all on A:l . - . _. __ W3QLW tried the key on CE3AG, Cll6WG, GW3AIIN, GW5BI, OQ5BU, ZSIBF, ZSlEB and ZS6OY. -· _. _ W7JLU made those ,;queaky noises in snatching LU2DS, LU5BM, KG6CP, ZLIMF and scads of VKs . _. _ . _ W2SXV has 86 countries on the band using Aa, hoasting of a new ,vi.de-spaced 4-clcment mecha nism . _. _._Also trying the microphone, W2GMM settled for VQ4HRP, VQ4GWB, OC2RS, ZE2JV, ST2CH, VP4TZ, HHIHB, HI6EC and YNlEP. Herb had to telegraph for • Have a squint at W. H. Malcoln'.i, G6WX, His Wor .ship the Mayor of Coventry, England, in full robes of office. This photo accompanied the application of G6WX for 'phone DXCC. June 1948 EAIFO (viaARRL) words "QSL via ARRL" should only be used by EI3U Dept. of Telecommunications, Institute of Science and Technology, Kevin St., W /VE stations. Under ordinary circumstances, Dublin, Eire cards for foreign amateurs should be sent direct to FKSAB J. Duplat, Noumea, New Caledonia the bureaus representing each respective country I3AXC Via Manzoni 20, Napoli, Italy - except in the cases where stations are operating ,J2ANT Navy 3923, FPO, San Francisco, Calif.. J4AAH Flight Lt. S. L. Somer, llq. BC Air, "under cover." The ARRL will accept cards to Iwakuni, Japan and from these stations. .16DKU {viaWIDKU) KG6AW/VK9 (to 2537 Hollins St., Baltimore, Md.) Tidbits: KM6AH % CAA, Midway MB9AG (via RSGB) Stat,h;t.ics from G8PP may knock the QSL halo l\ID5PS (viaRSGB) off the heads of rriany Ws. Les has QSLd 1300 OH2DT P.O. Box 12, Vaasa, Finland !>tations worked and claims the followin!!; returns: ON4DN Andenarde, Belgium PK6XA E. A. Krygsman, % NNGPl\I, Morotai. Wl, 100%; W2, 59%; W3, 81 %: W4, 50%; W5, N.E.I. 66%; W6, 55%; W7, 80%; W8, 60%; W9, 55%; ST2FU (via RSGB) W0, 100.%. Among the shortages are undoubtedly V06AF APO 677, % PM, New York, N. Y. VP2AG APO 855, Miami, J;'Jorida many lads who moan loudly when their cards to VP6HE Cliftonville, Fonte.belle, Barbados, B.W.I. rare DX go unanswered for a while and yet who VP6LD Laurie Dash, Marbill St., Bridgetown. are neglectful in answering cards themselves. Les Barbados, B. W.I. further compliments the ZL and ZS gang on their VP6PX Parochial Treasury, Christ Church, Bar- bados, B. W.I. high average of confirmations._._._ VS2CC VP6SJ Box 252, Bridgetown, Barbados, B. W.I. was on the air but a few weeks hefore Rhipping: V.P7NG Box 2003, Arlington, Va. hack to England for a 6-month leave. There he VP8AM Randall P. Stanley, Falkland Islands VQ3PYE Box .568, Dar-es-Salaam, Tanganyika operated as G3CYE. He'll be back in Kuala VQ4HRP H. R. Parnell, Box 1010. Nairobi, Kenya Lumpur soon again as VS2CC with 25 watts VQfiPBD Peter B. Dodd, P.O. Box 289, Kampala, and an HRO . _. _. _, KP4FJ is having a rough Uganda t.ime landing Idaho and Montana for his WAS \'R2AZ/VR1 Canton Island, Phcenix Group, Southwest, Pacific (28 Mc.) while IIK3AB would be satisf'tcd to set VR2BA (via ARRL) up a schedule with stations in the vicinity of VR5AF Box 25, Nukualofa, Tonga, South Pacific Norwich, Conn., on t,he same band._._._ VS7PS Box 349, Colombo, Ceylon VU2HS (via G2HS) VP6CDI and VR5IP warn that they'd like to be WICA/KP4 Hotel Normandie, San Juan, P.R. called at only the proper times or they'll close W6UNE/KW6 (via W6TI) their W files entirely . _. _. _ W60DD reports W7JEF/KG6 Clark W. C=, NAS Hobby Shop, Agana, t,hat ZDlWB's QST QTH resulted in a boomer Guam W7LBX/KL7 P.O. Box 219, Anchorage, Alaska ang - anybody get the lowdown on this station? W0SQS/Iwo CAABC, APO 86, % PM, San Francisco, . _. _. _ W7EYS states that terrific winds in Calif. most of W7 made many beams quite unmanage XAMC 18th Signal Co., APO 209, U. S. Army, able in the Contest, accounting for lowered scores Trieste, % PM, N. Y. C. YNIEP 153 AACS Sqdn., APO 3024, % PM, New in that area. Another argument for the under Orleans, La. ground antenna! [I've got the ditch all dug for YN2ACH Fernando Chamorro, San MarcoaJ Nica ours, boss. How about throwing your haywire rig ragua YSlV Guillermo Calderon, San Jacinto, San in with it? -.Jee11es.1 Quiet, Jeeves. You'd look Salvador pretty funny operating like a scared ostrich ZC6MF John Cox, APO, % 6th Airborne Division, . '.... _. _ D4AUU isn't Scotch, but he winces Haifa, Palestine ZKIAS Raratonga, Cook Islands when he sees so many W QSLs with up to 25!! postage on them. A penny will do, advises Don't thank Jeeves. Thank Wls FTX, KQY, W3DEJ. _._._Anybody wanting a W7QB/ QMI; W2s AKX, JB, HAZ, RYT, WFZ, WZ; h.'L7 card should try Wes' home QTH. He's back W3s GA, LTW, OP; W4KFC; W5s ASG, DTJ, home and wants to clear up the books._._. _ LKH; W6s CG, OJW, VAW, WNI, WSS, ZZ; KH6LF may be found on the low edge of 80 W8s AL, GG; W9CIA; W!Js CFB, WVS/5; searching high and low for New England WAS IIB9J; VR5PL. contacts - 100% QSL. _. _. _ Y1J7UU (13,998) On page 39 of May QST is a clarification of advised W9GMV that he will QSL all stationsin the ARRL QSL Bureau policy. The familiar (Cmiliniud nn paqe t 14) • Herc arc two prominent DXers who are almost a world apart - ordinarily. At the left is no other than W5ALA, ARRL West Gulf Division alternate director. Bcinjl; entertained in Jack's shack i• PA0Ul\f who stopped in for a vi•it while on his wav to PK. W5ALA can he heard holding his own on 14-l\Ic. 'phone when, •·•vcr the band is open for .DX. Watch for l'A0Ul\1 from l,i, new N.E.T. location. QST for Sw,piwL edlJ1.fJJL A "Q5-er" for BC-348 Owners HE "Q5-er" and 1.he "Lazy Man's Q5-er" This may not be the best method, but it is simple described in recent issues of QST I have and involves very little "messing" with the 348. Treally come into their own. The increased Incidentally, one might as well yank out the out selectivity gained by utilizing an i.f. channel of put tube in the 348, because after you use the 85 kc. has been used by many with excellent re- outrigger i.f. you won't go back to the original. - sults. Both of the Q5-er units described to date, CJ. M.-Kosolapoff however, will work only with receivers having i.f. channels in the 456-kc. range. Here are four . .. Building a Simple Convei·ter methods that enable the BC-453 (the 190--550 kc. o me, the obvious solution was to build a ARC-5 receivers) to be used with the BG--348, a Tsimple converter that would accept the 915-kc. receiver having a 915-kc. i.f. -- Ed. i.f. signal of the 348 and change it to some fre quency that is within the tuning range of the . . . by Adding Series Padders BC-453. Such a converter, utilizing a 12K8 as a HE use of the BC-453-B as an outrigger i.f. combined mixer-oscillator and standard 456-kc. T with the B0-348 presents a few problems occa broadcast-receiver coils (available as replacement sioned by the fact that the 453 tunes only the items in almost any store), was built on a stand range 190--.550 kc. while the BC-.'348 has an i.f. in ard 3 >'. 4 >: 5-inch utility box. Mica trimmers, the neighborhood of 91.5 kc. The following modi adjustable through grommeted holes in the side fication of the BC-4.53-B to make it tune to 915 kc. of the box and having a maximum capacitance of has worked out very well. 200 µµfd., were used to tune the mixer and oscil The slugs in the antenna, r.f., and oscillator lator coils. Other components, and the circuit, coils were removed. This can be done easily after were those employed in the converter portion of unplugging the coil strip. The stator leads from the receiver described recently in QST 2 and in the antenna and the mixer sections of the tuning the 1948 Radio .c1mateur's Handbook. Power for gang were clipped and a 150-µµfd. mica trimmer the converter was furnished by the same supply was inserted in each lead. By using heavy wires to used with the BC-453, the 24 volts a.c. being support the trimmers, good mechanical stability dropped to the 12-volt requirement of the 12K8 was attained. The main padder condensers (two with a suitable resistor. fixed micas, total 670 µµfd.) were removed. This Because of the relatively low frequencies in put the desired 915 kc. within the range of the volved, no particular precautions were necessary auxiliary padder and trimmers on the main con in parts layout and wiring, other than the careful denser gang. shielding of the lead that couples the output of Coupling to the BC-348 is made to the second the 348 to the input of the converter. No bugs or detector by wrapping a piece of wire (insulated) spurious responses were encountered, and per around the detector diode prong on the tube and formance of the "Q5-er" has been all that is leading the wire through a small hole drilled in claimed for it by other users. the front panel of the 348. This is more con No attempt was made to build the converter venient than making the lead come in from the into the dynarnotor shelf of the 348, or of the side where it would interfere with servicing or 453, because its chassis is so small that it takes aligning the 348. very little room on the operating table. There is Although this set-up works very well, it can be no reason why a 6K8 or other 6.3-volt converter improved by the addition of a. v.c. to the BC-453. tube could not be usecl with equal success. The The unused diode of the 453's second detector is 12K8 was used merely because it was on hand. - lifted from ground and a 2-megohm resistor is William W. Orr, W20WA inserted. The high end of this resistor is con nected, through 310,000 ohms, to a wire that is . . . Modifying the Coils carried through a hole in the chassis and into the HE tuning range of the BC-453 may be altered a.v.c.-m.v.c. switch of the BC-348. Here the T.. to cover the 915-kc. i.f. frequency of the BC-348 switch is revised so that the a.v.o. voltage of by the following method. Take off the coil-shield eit,her the 348 or the 453 may be used at will. assembly, and remove about half of the turns on 1 "The Q5-er," Rancl., QST, December. 1947. p. 18; Tech nical Topic•, B.G., "The Lazy Man'• Q5-er," QST. Jan .• ::. "An Amateur-Band 8-Tube Receiver," Goodman, QST, 1\148, p. 40. AuKUSt, 1946, p. 13. June 1948 69 the r.f. and mixer coils. (They will measure about To IHt ,o~LF. of ~{-inch diameter when enough turns have been 6AK5 JlJlfd. r:----~'.3~---, removed.) Take nff about the same number of ------: p~\ : turns on the oscillator coil. Loosen the coil slugs by melting the wax, and tune with the condenser gang until a broadcast station near 915 kc. can be heard on the 453. By use of the slugs, the main Jfo\: tuning-condenser gang,. and the trimmers, this .V, should be "duck soup" for the average ham. I I loqoo<>Jl. t.,: ______FRONT O .,l Since the 453 has to work only on 915 kc., no tracking problem is involved. If, however, you nare to take the trouble to trim the coils until accurate tracking is achieved 11cross the entire new tuning range of the 453, a nice spare b.c. 310-720 receiver will be the result. For those fortunate Kc. souls who possess a signal generator, this should he a lot easier. With the 453 working on 915 kc., remove the Off fon B.f.O. second-detector tube in the BC-348 and wrap a Sw. "' wire around the diode plate prong. Replace the Vig. 1 - Circuit diagram of a crystal-controlled tube in the 348, and rock the tuning condenser of oscillator used to beat with the i.f. output of the the 453 until the signals come rolling through. HC-348 to produce a signal in the tuning ra·nge of the In eases where a strong local broadcast station "QS-er." occupies 915 kc., the lead from the 348 i.f. output to the 453 input should be shielded. For peak The choice of the crystal frequency is not performance, the trimmers on the top of the 453 critical, as long as it will produce a beat that is can be tuned for maximum signal. within the tuning range of the BC--453. Do not, For added refinements, I found that the r.f. however, choose a frequency that will produce a 8tage in the 453 doesn't add anything to the com beat within 20 kc. of one-half of t,he i.f. frequency plete set-up other than noise. That stage was of the BC-348, as then all you will hear will be made inoperative by removing its coil. Coupling a steady signal from the crystal. It is well to pick from the !348 was then made directly into t,he out a clear spot on the dial of the BC-453, and mixer of the 453 by placing a wire near the ex t,hen get a crystal to snit. posed grid lead of the mixer tube. The coupling Almost any crystal will work well in the should be very loose for best results. Since the circuit shown. It is an adaptation from the cir 453 is for added selectivity only, it should be cuit used in crystal-calibrator units. I used 470 fairly obvious that the r.f. stage is not necessary. kc. as the crystal frequency, which when sub I also find that the high level of b.f.o. hiss can tracted from the i.f. frequency of the 348, pro be reduced considerably by placing a 3000-ohm duces a beat at 445 kc. That is about as close as resistor as a bleeder from the B-plus side of the you should come to the actual crystal frequency. b.f.o. transformer .to ground. This is about the No changes were made to the BC--453, except only way th~ b.f.o. plate voltage can be reduced, to tap the B-plus lead for the crystal oscillator because the skimpy amount of current drawn onto the screen-voltage connection at the rear makes the use of series dropping resistors futile. socket as shown in the diagram. Oscillator volt Marv Gonsior, W6l'FR age is fed to the antenna post of t,he 453 through ... Converting with an Extez·nal Oscillator HE !H5-kc. i.f. output of the BC-348 may be Tconverted to a lower frequency by beating it against the signal from a separate crystal oscilla t.or of suitable frequency. The two then can be mixed in the input of the BC-453 to take advan tage of the 85-kc. i.f. channel in that unit. This was accomplished using the circuit shown in Fig. 1, and the results compare favorably with t,he sensitivity obtained with l,he original "Q5-er" 1 and a BC-312. The oscillator and the The crystal-osdllator stage is mounted alongside of control circuits for the BC--453 were mounted on the «Q5-er" on a small panel that also contains the a small bracket and panel attached to the side h.f.o. switch, the gain control, and the 'phone jack. of the "Q5-er" as shown in the photograph. The method of coupling to the BC-348 is also shown. 60 QST for a 10-µµfd. condenser. Satisfactory mixing in the scribed, in which case the beat frequency may front end of the 453 was obtained With this value. be moved to almost any convenient point in the Coupling from the i.f. cha1111cl of the 348 to range of the 453. the 453 was made by shoving an insulated wire La8t but not least, be 1:Jurc that the plungers down inside the last i.f. transformer shield. in the i.f. transformers of t,he 453 are pulled all If desired, a self-excited oi:ldllator may be the way out to get maximum selectivity. - used instead of the crystal-controlled unit de- Philip S. Rand, IV1DBM ARC-5 Transmitter Modifications ROM several sources we have received in T is possible to obtain 14-Mc. output from the formation on various modifications that can ..I .BC-459-A and at the same time retain the Fbe made to the BC-457 and BC-459 trallil- gang-tuning feature. Amplifier padding eon 1nitters to improve their usefulness in the ham denser C'57 (the one with the locked shaft) is bands. Space does not permit inclusion of all removed, and ten rotor plates are removed from contributions, but the following have been se the other main tuning condenser. The plate coil lected as being representative of the more is then pruned down to 5.½ turns, and the tuning important changes. ·-··· Ed. slug is removed. A 35-µµfd. padder is substituted for Ca7, mounted with its shaft projecting Improved Keying UITE a few of the users of the "Co=and" Q transmitters seem to be experiencing keying troubles, as evidenced by the unusual number Fig. 3 - The revised of Official Observer notices I've had to mail dur grid circuit used when ing recent weeks. The responses to these cards the BC-459-A is used seem to indicate that the best way to , avoid for 14-Mc. output• .__New grid trouble is to key the oscillator plate and the connection amplifier screen simultaneously from a source of 200 to 300 volts. This should be accomplished by means of a relay to remove the hazard of having high-voltage on the key. The 0.05-µfd. through the side of the chassis. Plate-circuit condenser that is connected from the oscillator tracking is then adjusted by means of the new plate to ground also has caused keying troubles. padder condenser and the top turn on the coil. Its value may be reduced to 0,002 µfd. -· 'I' . .-1. The position of this turn can be adjusted to Previtt, W9UKT bring the tracking error to a minimum. To obtain greater r.f. voltage for the final 14-Mc. Output from the BC-459-A amplifier (to increase its doubling efficiency), the HE BC-459-A, originally designed for output t,ap at which the grid leak R74 and the grid Tin the 7-Mc. range, may be used to provide by-pass con.denser are connected is moved down output in the 14-Mc. band with slight modifica to the bottom of the coil as shown in Fig. 3. The tion of the LC circuit in the amplifier stage. value of the grid by-pass condenser, C53c, is changed to 0.00025 µfd. from the 0.05-µfd. value Open~ead •f X originally in the circuit. This change was neces sary to reduce the amount of chirp encountered 75ppfd. in keying. The fixed neutralizing condenser, 052, Add new that was connected from the cold end of the grid tunint Amplifier ~•tu condenser coil to the plate circuit was removed, as it is no longer needed.-···· Wt DX +8 Malcing Use of the Tuning Eye Fig. 2 ·- Substituting a 75-µµfd. condenser for the THE BC-457 and BC-459 transmitters wPrc original components permits the amplifier tubes in the · designed to work from a 24-volt ·d.c. supply. BC-459-A to work as doublers to 14 Mc. Under these conditions, the .1000-ohm resistor F'ig. 2 shows one method by which this may be between the 24-volt d.c. line and the cathode of accomplished. The original condensers, C61 and the "magic-eye" tube develops the co1Tect bias C65, are cut loose from the eoil, and a 75-µµfd. for proper operation of the tube in conjunction variable is substituted in their place. This, of with the built-in crystal calibrator. course, will not be ganged to the oscillator Most hams revise things so that the filament tuning condenser, but it can be resonated, sepa circuits operate from a 2-1-volt a.c. 1:Jource. With rately without undue inconvenience. - John T. a.c., the magic eye will not react. This can be McIntosh, WBZGO corrected easily, however, by the following June 1948 61 SHOR£ AFTE~ on the 7-pin power connector. (They are already connected to this pin in most units.) The effect of the fluctuating bias produced un 62 QST for Fourteenth ARRL Sweepstakes Results Biggest SS Yet-All Scoring and QSO Records Shattered ACH ~a. jor ARRL operating contei:;t, it se<'ms, within individual ARRL sections. All 71 of the provides the opportunity to report broken League's sections were active in this contest. E records of one sort or another. Those of us Attractive bronze medallions, engraved with the at, ARRL headquarters who are concerned with winner's call, are being awarded to 70 c.w. opera the task of compiling such statistics have come to tors and 68 'phone operators. The winners are aecept it, as a foregone conclusion that each those first listed in each ARRL section under the succeeding competition must inevitably result in heading "Scores." It took plenty of operating increased participation and higher scores. But ability to place on top in this SS and we heartily even our hard-boiled contest-checking personnel congratulate all those who qualified for t,he were somewhat overwhelmed bv the number of medallion awards. broken score and contact reco;ds made in the High C.W. Scorers What is the maximum score attainable in an SS contest'? We hesitate to venture an answer, but it. would appear that Vic Clark, W4KFC, came pretty close to the saturation point in the l947 fray. A score of 156,750 points, obtained through contacts with 923 different stations in 68 sections, makes him the undisputed 1947 SS leader and all~ time SS record holder. Vic's contact total figures out to 23.1 QSOs/hour, which is a record that will not easily be topped in subsequent contnsts. A 3.5-Mc. half-wave end-fed antenna, also used on 7 Mc., and folded doublets for 14 and 28 Mc., eombined with a VFO-controlled transmitter W6MLY, highest 'phone scorer, Santa Clara Valley ending up in a 257-B amplifier running 100 watti; Section winner. input enabled W4KFC to scoot, around the hands Fourteenth Annual ARRL Sweepstakes Contest, with maximum ease. The receiving end was held last November 15th-16th and 22nd-23rd. taken care of by an NC-100, two BC-348s and a Broken records were ''a dime a dozen," compared Gon-Set 28-Mc. converter. to any previous all-section type operating compe In the "place" position we find Larry Le t.ition. Kashman, W2IOP, who made a clean sw~ep of Participation in the 1947 SS set an all-time all 71 sections. His 882 contacts netted a score high. There were 1625 entries, 1282 from c.w. just a "nose" behind W4KFC-156,555 points. contestants and 343 from 'phone. Logs were The SS transmitter at Larry's shack consisted of received from all ARRL sections but the Philip a VFO driving a 4D32 or 4.-65, depending on the pines. band used. Receiving was done on a Collins 75A. All previous score records were smashed bv The "show" position was snared by W6HZT exceedingly wide margins. In past events, a c.~. with 893 contacts, 70 sections and 155,488 points. total in excess of 100,000 points was a notable Credit for this score goes to Cameron Pierce, achievement. In the Eleventh SS (1940) for W6HJT, operator at W6HZT during the SS. c~mple, three operators topped that mark; the Here are the remaining fifty c.w. scores over Twelfth brought eight such scores; the Thirteenth 100,000: W3BES 147,700, W9RQM 141,795, (1946) saw eighteen operators in the six-digit W9FOI 138,345, W6LDJ 137,568, W4KVX category. In this contest we find no less than 131,655, W5LGG 130,463, W8WZ 130,288, fifty-three operators in the hundred-thousand W9TWC/8 129,720, W3GAU 127,800, W9ERU class! 'Phone scores were likewise much higher 125,960, W9VSO 123,752, W6AOA 122,648, than ever. In 1946 eight voice operators made WIRY 121,958, W2SSC llfi,790, W3BXE 116,- scores above 30,000 ·points. Thirty-five entrants 115, W8ROX 116,025, W7FZA 115,834, W4LOI topped that figure in this SS! Winners As in other ARRL all-section contests, compe tition for awards in t.!1e Sw~cpstakes ii; only •· 7 " 8WZ, Ohio c~w. winner. June 1948 114,972, W5KC 114,540, W9FJB 114,240, W3GHM 113,398, W3FQZ 111,840, W2PGT 111,555, WSUWM 111,178, W9CYU 108,800, W2PWP 108,675, W2A YJ 108,150, Wf1YCR 107,669, W2CZO 107,640, W0JNC 106,930, W5LW 106,750, W9GRV 106,250, W2QCM 105,543, WlBIH 105,225, WlVDY 105,105, W9VES 105,060, W9WFS 103,673, W0DYX , 103,673, W0DNW 103,515, W3KT l.03,360, W9DUY 103,155, W2JAG 102,938, W9Nll 102, HSO, W3DPA 102,510, W2SAI 102,255, W2HEH 101,600, W3JTC 101,400, W8RCN 101,238, WILWA 100,800, W4KFT 100,750. In Canada the highest-scoring contestant was VE3KE, with 567 contacts, 68 sections and 96,050 points. VE7ZM scored 85,818 from 5[}5 QSOs with 69 sections. Third-place Canadian was VE6AO, who worked 585 stations in 66 sections for 75,372 points. Other high VE scores: VE3EF 75,040, VE3EK 74,370, VEITR 70,784, VE7ALE 65,650, VE3GT 61,840, VE3AEM 59,875, VE3AGX 55,957, VE7EH 52,416, VE3AilV ,52,227, VElIU ,51,910, VE3JJ ,50,530, VE5MQ 50,111. In the previous contest there were ten stations in the over-700 contacts class. This SS :;aw ten operators topping 800 QSOs and eleven with contact totals over 700. As has already been men tioned, W4KFC set a new SS record .. by working 923 different stations. Next in line we find W6HZT 893, W2IOP 882, W4LOI 868, W9FOI 862, W3BES 844, W9RQM 826, W9FJB 817, W0YCR 810, W6LDJ 802, W4KVX 786, W9ERU 753, W9TWC/8 752, W5LGG 749, W8WZ 747, W8ROX 720, W0LLN 716, W6AOA 711, W2SSC 709, WIRY 708, W70NG 703. Leaders in Sections Worked Following 1946 pattern, the distinction of hav ing worked all sections was shared equally be tween 'phone and c.w. participants. W8BKP and W8HUD on 'phone, W2IOP and W6MUR (m ('.w., worked all 71 sections. The Philippines sec tion was missed by numerous other contestants. The following each worked 70 sections: C.W. - WlOJM, W2AYJ, W2CWE, W2FBA, W2PWP, W3BES, W3BVN, W4BRB, W5LGG, W5LW, W5NIW, W6EPZ, W6GWW, W6HZT, W6MVQ, W6NNV, W6WIP, W70NG, W8BWC, W8.JM, W8WZ, W9FJB, W9VFZ. 'Phone - W5LRE, W8BWC, W9NDA, W9RBI. Leading 'Phones The West CoaRt walked away with top hon ors in the SS 'phone competition. Californian W6MLY took advantage of the low-power multi plier, chalked up the highest total, 65,540 points, through contacts with 883 stations and 69 sec tions. W6AM was a close second with 03,717 points, 477 contacts, 67 sections. Don worked more stations than the leader, but he was edged out in the scoring by W6MLY's multiplier. QST for CLUB SCORES Club score CJ. w. Winner '.PhonB Winn.Br Frankford Radio Club (Phlla.) .....•. 2.670,R77 . W:lBblS W3DHM llloomlleld Radio Club (N.J.) ...... ' 1,438.628 W20LO 0 1,149,780 W4KF'C b?!~:::~ct~~ ,~d~1utsn: .·::: ... . 700,824 Washington Radio Club (Wash., D.C.) .. ~~]:~)/II San Antonio Radio Club ...... , .. ~~~:~~~ W5LGG North Suburban Radio Club ...... 603.1.56 W9PJB W9CMG Nortllern Califorula DX Club . 601,837 W6TT W6IK<..! m-Ray Radio Club .•.... ' .. ' ... '' ..... ' .. . .55.5,033 WlVDY WIPKV M!lwaUkee Radio Amateurs' Club (Wis.) ...... 504,f5:l9 W9VSO W9PTE Greater Cincinnati Amateur Radio Assn ...... ~92,053 W4I W60GZ, fourth in last year's contest, moved up to third this year - 62,846, 471 contacts, 67 sections. Also worthy of special mention was W6QEU's fow·th-place score of 60,375 (353 contacts, 69 sec tions). Additional outstanding scorers: W9NDA 57,820, W2NSD 57,052, W6HAN 59,400, W9RBI 54,950, W4YNQ 54,805, W8HUD 52,966, W6CHV 44,370, W9RNM 43,112, W9KYM 40,732, W2TUK 40,078, W2RVC 38,464, W4JYB 38,464, W5KAU38,400, W00MG38,080, WlATE 37,672, W6IKQ 36,918, WlBIB 36,696, W2EGG 35,979, W0GZD 35,100, W7KRM 44,880, W9QIX 32,886, W3DHM 32,572, W8TRX 32,488, W4AQR 32,160, W3FUV 31,850, W8SDD :n,626, W2JKH 31,490, W8BKP 31,240, W5FH 30,954, W0RQK 30,656, W8PXP 30,132. W6AM with 477, W6HAN with 455, and W2NSD with 421 contacts topped all previous stations-worked records. Other leaders. were VE3KE, highest-scoring Canadian, Ontario c.w (Continued on page 118) winner. June 1948 65 Hints GIid Kinks ~ For the Ex erim.ente , ---· CLEARING JAMMED PULLEYS the plate tank. The whole operation from start ONE of my antenna pulleys had gotten gummed to finish took only a few minutes. With 700 watts up or rusty and was becoming hard to oper input and 100% modulation, the 813s were reallv ate. The pulley was at the top of a 42-foot mast stable for the first time. .. that could not be lowered or climbed. Here's a hint Homemade swinging links for the neutralizing t-0 others faced with the same unhappy problem. leads were constructed and installed in the 10- I folded a piece of waxed paper diagonally a meter final and also in the 20- and the 75-meter couple of times, forming a triangular sack. I then finals. All three have been working for over a year poured several ounces of heavy motor oil in the and much more satisfactorily than any other sack, gathered the top together with string, and method yet tried here. lashed the whole sack to a point on the antenna - Philip Rand, Wt DBM A GRID-DIP METER FOR V.H.F. F you do much construction work in the v.h.f. I range, you will appreciate the need for a sensi t,ive grid-dip meter to check the resonant fre quency of an unknown tuned circuit. It must be small enough to couple into some of the rather minute tuned circuits that are used. To fill such a need in the Headquarters lab, the gadget shown Fig. 1 --· A clever method of oiling a pulley at the top in Fig. 2 was built. It is patterned after the onf> of an antenna mast. A breakable sack is made of wax described in QST recently by W2BFD.1 paper and is then filled with oil. It is smashed against An acorn triode in an ultraudion circuit is the pulley block with a quick yank, drenching the ·block (Continued an pao• 118) with the oil. · haJ.yard that I knew I could pull through the pulley. The halyard was then pulled until the sack was four or five inches from the pulley, as shown in Fig. 1. A quick yank on the halyard then smashed the paper sack, causing the oil to drench the pulley block thoroughly, giving it the bath that it needed to clear up the trouble. - Robert E. Barr, W5GHF NEUTRALIZING THE 813 ,\FTER many hours of trying in vain to neutralize .tl. a pair of 813s by conventional methods and never knowing whether I had too much or t.oo little capacity, I finally decided to try inductive neutralization. A one-turn link was wound around the center of the grid coil with "bell" wire and 11··~+ Ci71 \( - f. 5 V. + brought over to the center of the plate coil with 70-ohm Twin-Lead where another one-turn link Fig. 2 ··- Schematic diagram of the v .h.f. grid-dip was constructed. With grid drive on_ and plate meter. power off, the final grid and plate tanks were C1 -11-µµ{d. "butterfli" variable (Johnson 160-211). C2 -50-µµfd. ceramic lNational XLA-0). tuned to resonance. A 60-ma. bulb coupled to the Cs -- 680-µµfd. mica. plate tank almost burned out. The swinging link R, - 68,000 ohms, H watt. neutralizer was then slowly pushed into the L1 - 2 turns No. 12 wire, lH•-inch i.d., turns the spaced ½2 inch. Ends of coil extend % inch center of -the plate tank, and bulb grew past o.d. of coil. ' brighter so the 70-ohm Twin-Lead connections RFC1, RFC2, RFCs - l-µhy. r.f. choke (National R33). to the link were reversed and presto, the bulb S11.-n - D.p.s.t. "push-button" type toggle switch, grew dimmer. The swinging link was pushed in a normally open. little at a time until the 60-ma. bulb went out 1 Williams, "A Bandpass Converter for 144 Mc.," QST, completely even though it was tightly coupled to March, 1948, p. 34. 66 OST £or Correspondence From Members- 'fhe PublisheH of QST aosume no responsibility for statements made herein by correepondenta. PUBLIC SERVICE [have you ever been in a Sweepstakes Contest?!, and moun tain climbing to satisfy his need to dominate and excel [dust 1810 Spear Street, Logansport, Indiana off that DXCC certificate!," Editor, QST: Should we tell the psychologists about ham radio? I think we hams are making a mistake in the arguments -Ben W. Roberts, W9IEU we emphasize to justify our occupancy of a part of the radio spectrum. We place far too much accent on providing emergency communication and on the training of code operators for the military services. If we continue to base WASHDAY BLUES our case on the furnishing of these two services, we are going 3 Hull Ave., Dover, N. H. to"wake up some fine morning and discover that the·ground Editor, QST: has been cut from beneath our feet. Fortunately, there i• How could you? Tskl Tskl To print 1mch a thing! "The a great contribution that our hobby makes toward the wel grea,,e is wiped off with a clean linen handkerchief after drill fare of our coantry, a contribution that has no danger of ing is complete" (page 67 of May QST). A linen one, no becoming obsolete and that does not permit of belittlement: lea.s, and after we wives have tried so hard to train our amateur radio attracts many young men into the field of science. husbands properly. Especially those so alarmingly infected That idea is not new, and it may not seem important, but with "virus radio." it is. Consider how many boys you know personally whose Would you please amend your statement'/ interest has been won from marbles and kites by the magic - Ernestine Nutttr, WtKKT's XYL of ro.dio. Recall how those boys literally "ate, drank, and [EDITOR'S NoTE: This practice is suggested only if the job Blept" radio, putting forth efforts to know more of this sub isn't done on the dining-room table, in which case the table ject than their teachers would never have believed possible. cloth will serve just a.s well.] Remember, too, how they graduated from high school and went on to engineering schools to learn more and more of this fascinating subject so that it now would take a wise 1 1 SWITCH TO SAFETY man to label the more correctly ''vocation'' or ' avoca.tion. ' Do not forget that these same men are the ones who made 78 Clinton Avenue, Eatontown, New Jersey great contributions to the discovery of radar, frequency l!:ditor, QST: modulation, television, and facsimile transmission. No one Having just missed being a candidate for the Silent Keys can evaluate just how much they contributed, directlv and column, I can fervently say "Amen, Brother" to your edi indirectly, to the fearful discovery of the atomic bomb. torial on safety in April QST. In particular, I would like to There is no comparison between the work done by a man endorse your statement, "But no construction code can who is really interested in what he i• doing and that done by protect you adequately, since components can fail and cause another who is simply performing his task for money. This death-dealing voltages to appear at unexpected places." is particularly true in the field of science, for here a man Here's my sad tale: The rig is a BC-610D. I set about in must have a consuming interest in what he is doing if he is to creasing the antenna coupling. In this I followed the stand rise above the mediocre. Interest, though, is something you ard tune-up procedure for this equipment, turning off the cannot b11y nor force. It must grow of itself, naturally; but plate power switch before opening the transmitter lid - too man.v obstructions must not be placed in its path, espe which as a further protection is equipped with an interlock oiall.v at the beginning when it is weak. switch. The plate tank was then stone cold and I adjusted Military preparation is rapidl.v moving from the para.de the antenna link. Turning power on, I found that I had not ground to the 1.. horatory. A country must be in the van increased the coupling enough, so I repeated the foregoing guard scientifically il it is to be safe from attack. No effort is procedure, but this time the tank was hot! 2500 volts of too dear that succeeds in attracting young men into the d.c. seized my right hand and tossed me into the air. My scientific field. wife, who was seated near me, reports that she heard a siz.. Amateur radio, then, is the cand.v-coating on the pill, the zling and looked up to see me rise to about three feet above carrot held in front of the donkey, the rose-strewn path that my chair and slam down again with a bang. With great leads directly into the hall of science. It would be a foolish presence of mind she pulled the power plug from the wall and short-sighted government that would do anything to before attempting to help me, but fortunately ther,onvulsion injure such an important factor in the military and economic ,,f my arm had pulled the plug-in tank coil from its base, thus future of our co11ntry. releasing me from the power after the initial jolt. For the - John T. Frye, W9EG1' past two weeks, my right hand and wrist have been swathed in bandages. The doctor says that 1 am very fortunate in that none of the tendons wa., damaged, but there was a deep burn and healing is a slow process, so it will be some "ALL THINGS TO ALL MEN" time before I have full use of the injured hand. Lostant, Illinois Investigation of the transmitter disclosed that the plate Editor, QST: power and interlock switches control the actuating voltaa;e Howard Whitman, writing in the March Reader's Digest, of a relay in the primary feed.line of the plate transformer. aaye, plus some side remarks of my own: In some manner or other (probably because of a strong are) "Every man ought to strive for at least four satisfying the contacts of this relay welded together and failed to re kinds of play•..• !<'or example, he might have a stamp lease when the switches were turned off. Since many other collection to grat;fy his acquisitive instinct lowning a nice hams are using various models of the BC-610, I suggest that piece of radio gear should take care of that), carpentry to you publicize this potential danger. I have learned from fill his creative urge [is there any better way of filling the Signal Corps personnel that freezing of the relay contacts creative urge than by assembling a contraption for long ha., been a frequent-enough source of trouble in this trans- distance communication?], tennis to get out his aggressions (Continued on page 118) June 1948 67 F. E. HANDY, WlBDI, Communications Mgr. GEORGE HART, WlNJM, Communications Asst. J. A. MOSKEY, WlJMY, Asst. Comm. Mgr. • A. F. HILL, JR., WlQMI, Communications Asst. ALBERT HAYES, WlIIN, Natl. Emerg. Coordinator LILLIAN M. SALTER, Communications Asst. Harmonic Trouble? Cross-Band Calling? Full Call Identification Required. W9CIH in Why, we ask ourselves, is it so common in our writing us recently asks, "Have you noticed of voice operations to hear calls of "CQ ten," "Cq late the tendency of many fellows to drop the W .wventy-Jive," "Cq two'' and the like? Such oft prefix when signing their calls'? This is geUing repeated calls seem most unnecessary when a worse right along." FCC requires the complete simple "call to auy station" will bring answers. transmission of call identities and cites amateurs Tu it perhaps because so many of us working the who omit the W, K, or numeral prefix or who, 28.5-29.7 Mc. subband have two-meter harmon when in voice co=unication, use descriptive ics or harmonics of other bands't Our local 144- words such as "double" or "triple" as a sub 148 Mc. band seems infested with unnecessarily stitute for repeating the letters of their proper loud signals whose origin is some ten-meter trans call identities, where the same letter exists more mitter. We have even called stations mistakenly t,han once. FCC does provide in §12.82(d) that because of this condition. Is it the same in other when using telephony, phonetic aids to identify cities'? But surely the cure for improperly strong the call of the station may be employed. Both the harmonics, which none of us can tolerate in the call of the station called or being worked and the face of a, growing Lelevision population, is a heart call assigned a station are to be transmitted "at to-heart session with our transmitter to give it a t,he beginning and end of each transmission and real engineering going-over for maximum sup at least once every ten minutes during every pression of harmonic radiation. Faraday-screened transmission of more than ten minutes' duration. coupling coils and links and a completely In the case of stations conducting an exchange of screened-in transmitter (see cover May '47 QST) several transmissions in sequence, with each rnay be honest answers to keeping our harmonics transmission less than three minutes' duration, down as required of all amateurs under FCC the call of the co=unicating stations need be §12.133. We amateurs, of course, do object strongly transmitted only once every ten minutes of opera to television allocations made so that we cannot tion as well as at the beginning and at the work without interference when we are observing termination of the correspondence." the highest engineering standards, and we raise Local Work on DX Bands? Rag-ehewing in t.his sub.iect. so we can continue our record of keep casual (lSOs is an enjoyable pastime engaged in ing harmonics more than ordinarily well-sup by about 92% of all amateurs at a given ti.me. pressed and under control. Class B operators express a 76% interest in Returning to the subject of calling practice, it working DX. DX as well as rag-chewing has a seems to us that it is just as unnecessary to name universality of interest. It requires lots of listen the frequency band we are working on in ordinary ing on the principle that "You have to hear them amateur voice work as it would be in c. w. calling. before vou can work them." DX work on different We never need to state the baud on which replies bands is limited to the times of day when propa to a call are expected excepting in the rare in gation conditions are favorable. When DX is not stance when one is working cross-band and ad coming through, most of the gang engage in rag vising the specific frequency for reply. The chewing. Many maintain transmitters on non-DX June 1948 69 TRAFFIC TOPICS 'rhls month brings us to the close of the very BUSS POUNDERS LEAGUE succe.ssful 1947-48 traffic season. The past March Tl,affic several months have seen us improve the opera Extra. Del. Call Orig. DeT.. Rel. Cr«lit Tota.! t.ion of our message-handling system. to a high W0HMM 26 37 972 21 1056 degree of efficiency. There is room for improve W7CKT 24 84 991 1049 ment, however, and we should take stock of our W5LSN 5 58 8.'10 l.i4 947 operating practices, our net organizations and our W2TYU 27 24 788 1 840 W4PL 11 18 622 8 657 station facilities during the summer months. W9EVJ 6 as 570 21 635 Now is the time to start laying plans for the VE3ATR 489 37 2:l l 550 coming season. Line up your stations, outlets, W2QYZ 17 18 488 8 531 and other oplilrating details beforehand so that The following make the BPL with over 100 we can make 1948-49 the greatest t,raffic season "deliveries plua extra delivery credits": WlFGT 218 wsscw 194 W3ECP 111 on record. WSIHR215 W6CMN 138 WSUPB 109 WlJCK 205 W1AW118 W9LFK 106 The Swing Shift Net, which covers New W9SYZ 199 VE3DU 118 W6RXT 104 England, has shifted frequency to 7280 kc. This W2RTZ 117 group meets Monday through Friday at 1:00 P.M. A message total of 500 or more, or 100 "deliveries EST for those who are working night shifts and plua extra delivery credits," will put you in line for can operate only during the daytime. a place in the BPL. The Brass Pounders League listing is open to all operators who qualify for title monthly "honor roll.'' Traffic Outlet goes on its summer schedule on June 1st. Continuing operation on 3705 kc. at 10:00 P.M. EST, the gang will meet on Monday, VE3BCP in Ontario has organized a network of Wednesday and Friday. operators who are employed at radio range sta tions in Canada. An excellent tie-in with the Northern New ,Jersey Section has supple Beaver Net is available througl_l VE3ATR. The mented its 80-metcr schedule with a 7070-kc. net. group operates on 7167 kc. at 7:00 P.M. EST using The latter meets Monday, Wednesday and Fri the general call "QDT." All radio-range-station day at J:30 P.M. EST and N.N.J. stations arc operators in Canada are urged to contact VE3- invited to check in at any time. BCP for further details. The New Hampshire Section now has good coverage throughout the state. The 80-mcter C.W. Net on 3685 kc., the 75-metcr 'Phone Net on 3980 kc., the 10-metcr 'Phone Net on 29,200 kc., the 6-Meter 'Phone Net on,,52 Mc., and the 2-metcr 'Phone Net which is now in the process of organization, provide one of the bel:!t coverages of any section. Trunk Line "I,'' the all-Canada trunk, is do ing a bang-up job from coast to coast. Every province is now represented. Traffic for Canada may be routed through TLI for speedy delivery. The summer schedules of all operating traffic nets would be appreciated for our files. A radio gram to Headquarters will do the trick. "TRAFFIC" HANDLED BY GLACIER RADIO CLUB 'fhe Big Mountain Ski Tournament on March 7th gave the Glacier Radio Club an excellent opportunity to test emergency equipment. Faced Introducing W2ANW. T. J. "Tom" Lydon is the kind with the problem of controlling two-way traffic of amatear who helps to keep the wheels of traffic and over the narrow one-way road leading to the ski other CD organization humming. W2ANW is ORS, OPS, RM, 00, Assistant SCM, OBS and EC. He's a course, the local sheriff's office requested that the regular on the Northern New Jersey Net and NCS one club provide communications between the main night a week on TL "C" and Traffic Outlet net. His highway and the top of the hill, a distance of operating ability is well above par as att-ested to by his 35-w.p.m. ARRL Code Proficiency Certificate and about four miles. W7BHP'a BC-654 was set up at membership in the A-1 Operator Club. the highway position and W7LOB's 10-watt 70 OST for portable was used at the upper end. Communica t.ion was !',Stablished according to plan on the 3.5-Mc. band using .both 'phone and c.w., and continued for seven hours. W7AFM stood by with his regular station in Whitefish, Montana, and relayed for the two portable stations during a period of poor signals. During the operation approximately 200 auto mobiles were handled in each direction without any traffic difficulties, and both the sheriff and the management of the ski tournament expressed satisfaction with the efficiency of communica tions. Amateurs taking part in the operation were W7s BHP, EGN, AFM and LOB. TRAINING AIDS The rules for use of motion picture films from the ARRL Film Library have been revised Visitors to the Florida State J!'air gather around slightly to accommodate those clubs who must W4DUG, a station well known to traffic-handling ama rent projectors, or who consider it not worth teurs. Operated by members uf the Tampa Amateur Radio Club, this station has seen annual service at the while to set up a sound projector and associated fair since 1935. A well-planned series of schedules tying equipment for the benefit of a film lasting only into regular amateur traffic nets allowed the W4DUG a few minutes. group to handle just under 3000 messages in ten days' operation this year. Transmitters running 400 watts on In the future, affiliated clubs may book more 3.5 and 7 Mc. and an IIQ-129X receiver comprised the than one film for a single showing if they request main station equipment. it far enough in advance. To schedule two films for a single showing, your request must arrive here between one and two months before the DX CENTURY CLUB AWARDS films scheduled showing date. To schedule three DXCC certificates based on postwar contact. for a single showing, your request must arrive with 100-or-more countries bave been issued to the here between two and three months before the amateurs listed below. The countries-worked totals scheduled showing date. Clubs who make double indicated have been oertified by examination of written evidence under the a.ward rules as published or triple advance bookings in accordance with in March 1947 QST. these rules may not book additional motion HONOR ROLL picture films in the interim. Two or more films WlFH ••••••••••• 186 G6ZO ••••••••••• 166 whose running times total twenty minutes or G2PL •••••••..••• 173 W3BES •••••.•••• 164 W6VFR •.•• , •••• 172 W3GAU ••••••••• 162 less are considered a single film for booking W8HGW .••••••••171 WlCH ••••••••.•• 160 purposes. The mimeographed rules have been W4BPD •.•.••••. 166 W2BXA ••••••••• 160 modified to incorporate this new policy. NEW MEMBERS The restrictions on mot.ion picture films do VE7ZM ••••••••. }36 W6KUT ••••.•••• 104 W2NSZ.'••••.••• 127 W01ilQ0 •••.••.••• 104 not apply to film strips or slide collections. W6DI •••.••••••• 183 VK2DI. ••.•••••• 103 One motion picture film and fifteen tapes W6LGG ••••••.••• 116 W8ERA ••••••••• 102 ZLlBY ••••••••••• 114 W9FJB ••••.•••••• 101 have been added to the list of ARRL Training HB9D0 .••••••••• 113 W6POZ •••••••••• 101 Aids available. Brief descriptions follow: W2RGV ••••..•.• 109 W30P ••••••••••• 101 OKlLM ••••••.••• 108 WlNMP ••••••.••• 101 /?24. "Techniques of Hand Sending." 16 mm. ON4JW •••••.•••• 108 W6VBY •••.•.•••100 sound. U. S. Navy. 9 minutes. ZL2QM ••••••••• 107 KP4KD •••••••••• 100 WlCLX .••....•.• 107 mv ••••••••••.•• 100 TP11. Inked tape suitable for use on TG-10 or W2PWP •.•...•.. 104 TG-34 keyers. Code characters F, G, H, M, J, R ENDORSEMENTS and U. W6SAI .••••••••• 166 W9KOK •••.••••• 122 TP12. Code characters B, D, K, N, T, V and Y. WSASG ••.•••.•• 160 W6LER •••••.•.•• 121 W7FZA ••••••••. 142 W3EVW •••••.•.• 120 TP13. Code characters 0, E, I, L, 0, S and G. zs2x .••.•.•••••• 141 W6BAM •••....•• 112 TP14. Code characters A, P, Q, X, Z, 4 and 5. W4CYU ••..••••• 141 W4DKA ••.••••••• 111 WlME .•.•.•.•.•• 140 WlENE ••••••••.•• 111 TP15. Code characters 1, 2, 3, 6, 7, 8, 9 and 0. Wl!GKS .••••••••• 130 TP16. All code characters for 5-w.p.m. trans- RADIOTELEPHONE mission. HONOR ROLL TP17. All C()(;ie characters for 7-w.p.m. :trans WlFH ••••••••••• 148 W2BXA ••••••••.• lll wi1cx ...... • 130 w2zw •.••••••••• 110 mission. W4CYU ••••••••• 130 WlNWO •••.•••••• 110 'l'P18. Code groups for 10-w.p.m. .trans WIHKK •••.•••.•• 124 W6DI. .•••••••••• 110 mission. G2PL •••••••.•.•• 119 VQ4ERR •••••••• 109 TPJB-25. Tactical messages for transmission NEW MEMBERS speeds beginning at 12 w.p.m. with TP19 and G6WX •••..••.••• }Ol increasing to 20 w.p.m. with TP25. · June 1948 71 WITH THE A.E.C. speed" net for the purpose of assisting interested The N. Y. C.-L. I. Emergency Corps, under the a1:13-teur~ to attain increased code proficiency leadership of SEC W2BGO, has conducted a Wlth a view to the supplying of improved emer series of intersection tests between their 144-Mc. gency operating facilities. This net operates on group and the v.h.f. groups of Newington, Conn., 3791 kc. each Wednesday evening at 7:00 PST. Hartford; Conn., and Binghamton, N. Y. via t.heir respective 8.5-Mc. nets. These tests have The Suffolk Cmmty (New York) Emergency ?rought to light the limitations of the groups Corps holds weekly drills on 8600 kc. on W cdnes mvolved as well as their points of excellence and days at 7:30 P.M. EST. Traffic handling is the it is anticipated that, as further fa>.sts are' con "order of the day" so that the gang will be best ducted, the speed and accuracy of such internet prepared to handle t.hird-partv traffic when t,raffic handling will be greatly enhanced. and if, disaster strikes. · ' . The Radio Club of Arizona (Phoenix) has The Milwaukee AEC group has 27 active formed a completely emergency-powered net i;t,ations, all crystal-controlled, on 144 Mc., and operating both 'phone and c.w. in the 8.5-Mc. holds weekly drills. It is anticipated that the hand. group will soon extend its coverage into Southern Wisconsin and Northern fllinoiR. ARRL Regional Co6rdinator WILKF has announced the organization of the Connecticut . A s~mulated emergency test conducted by the River Emergency Net, dedicated to the service Washington AEC on March 7th brought out of the U.S. Weather Bureau's manv river-observ some 1.50 member stations operating on all ing stations along that stream anci"its tributaries. hands, both 'phone and c.w. Both the AEC Weather information and reports of flood con members and the members of the section traffic <:litions along the river are handled during drill net found the test valuable. each Wednesday evening, and if the old Con necticut decides t,o go on a rampage again it Communications Department Operating Aid will ~d the gang on 8580 kc. ready to hPlp Number 4, a eard describing the ARRL Emer tame 1t. gency Corps and giving suggestions for your emergency operation, is presently available on When the Milwaukee Railway found itself request from ARRL Headquarter~. without communication between Roscoe and ILLINOIS AMATEURS SERVE AGAIN Aberdeen, S. D., on March 26th, t,he South When a tornado struck Fostersburg, Gillespie, Da~ota gang really "came through." Although and Bunker Hill, all small towns in Southern their traffic route was eircuitous, some 700 miles Illinois, on the morning of March 19th, arnatcur of routing to cover t,he 50 miles between Roscoe radio once again had an opportunity to provide and Aberdeen, W0BLK, WOOLB. and W0UVL emergency communication. Groups comprising handled the railway's traffic in the finest tradi both home stations and portables, rushed to the tions of public service. scene by emergency-minded amateurs normally residing outside the affected area, set up f~r The Society of Amateur Radio Operators, of operation within a few hours after the furv of the San Francisco Bay area, operates a "slow- the storm had been &'Pent. The latter included W9KQL/9, W9UQT /9, and W9EOP /9, who operated at Bunker Hill; W9VOA/9 at Gillespie; and W9JFG/9 and W9UHD/9, who operated at hoth Gillespie and Carlinville through which the majority of t.he emergency cornmunications were being routed. These intrepid amateurs operated under a difficulty new to most operators -- the power companies were bringing power lines into the disaster zone without insuiators and the QRN was terrifie! At 7:30 P.M. on the 20th it developed that the telephone company had restored normal service and the hams shtit down for a hard-earned rest. The Salvation Army, Red Cross, American Legion and VFW provided food and drink for the amateurs and W6YMY/6, station of the Pomona (Cal.) High reams of t,raffic for their t,ransmitters, and the School Radio Chili, tton location" on a combined cmer• Illinois State Police col:ipcrated with the operators l!!'~cy test-field day excursion during Easter vacation. (~ef Operator W6ARV is in the operating position, in every possible way. with other club members looking on. Among the stations outside the emergency 72 OST for area who contributed to this succ<','lSful demon were received in due course. Both WlLRZ and stration of what amateurs can do in a com W6VUO independently had chosen 7040 kc.! munications emergency were: W9s AEX, AEZ, We'd hate to figure the odds on such an occurrence APX, BIK, BMV, COW, CRM, CTZ, DHW, repeating itself, considering the countless fre EBX, EEM, ENI, FIN, HSB, !ER, ILII, quencies that might have been selceted! KCW, KDU, LXT, MJV, MXD, NRF, NSD, OGE, PEK, PLS, RPL, RVT, SSP, YJH, ZSN; W0s CVU, DUD, FQY, GOT, JRJ, KQX, KSR, OML, RNF, and WRT. A.R.R.L.-AFFILIATED CLUB HONOR ROLL Y.L.R.L. NOTES The combined Membership Drive-QSO Party All members of these clubs are of February, 1948, resulted in 59 new member8 ARRL members for YLRL, including several in countries new The Above 100 Club, Winnipeg, Man., Canada to the organization. Prizes went to: Enid Aldwell, Albany Amateur Radio Club, Albany, Ga. ,\mateur Radio Club of Savannah, Savannah, Ga. W6UXF, chairman of the winning district (6th) Amateur Radio Transmitting Society, Louisville, Ky. which gained the highest collective score; Lou Astoria Radio Club, Woodside, N. Y. Littlefield, WlMCW, for the highest 'phone-only Bartles,ille Amateur Radio Club, Bartlesville, Okla. Hcore (and highest individual score); Clarice Chattanooga Amateur Radio Club, Chattanooga, Goodman, W7FTX, highest 'phone-c.w. score; Tenn. Enid Aldwell, W6UXF, highest c.w.-only score. Che•ter Radio Club, Chester, Pa. Louisa Dresser, W200H, and Lillian Ruocco, Cle,•eland Amateur Radio Society, Cleveland, Ohio Conneaut Radio Club, Inc., Conneaut, Ohio W2PMA, were given special recognition certif Connecticut Wireless A$sociation, Newington, icates for outstanding work in the membership, Conn. drive, as was Helene Leonard, W6QOG/MBD, CQ Radio Club, Torrington, Co11n. Detroit Amateur Radio Association, Inc., Detroit, who is NCS of the 10-Meter Net. Mich. The Detroit M.etropolitan Radio Club, Detroit, The next YLRL QSO Part,y will be the "C.W. Mich. Spree," June 3rd, 4th and 5thon3.5, 7 and 14Mc. Fairmont Radio Club, Fairmont, Minnesota The 56 Mc. Minutemen, Medford, Mass. respectively. This activity is designed to help YL Frankford Radio Club, Philadelphia. Pa. operators find each other on the c.w. bands so narden City Radio Club, Garden City, N. Y. that those working toward the WAS/YL Certif Grumman Amateur Radio Club, Bethpage, L. I., N. Y. icate may catch certain elusive states. Iowa-Illinois Amateur Radio Club, Burlington, Iowa BRIEFS ,Jersey Shore Amateur Radio Association, Long During one of his daily skeds with W6WII on Hranch, N. J. fvfa11i Amateur Radio Club, Wailuku, Maui, T. H. 7 Mc., Bob Higgins, W6WQV, was telling of a Mount Shasta Amateur Radio Club, Mount Shasta, dream he had had the previous night in which his Calif. trailer home had caught fire. He had hardly Newington Amateur Radio League, Newington, finished the description when he heard his XYL Conn. Northern California DX Club, Inc., Oakland, Calif. calling for help. Glancing around, he beheld '•.fnrthwe st Amateur Radio Club, Des Plaines, ItL flames leaping to the ceiling! The trailer gasoline Order of Brass Pounders, Chapter 3, Kansas City, stove was belching 89 flames which threatened Mo. . Pioneer Radio Club, Fremont, Nebraska to fulfil Bob's dream. Little damage was done, Providence Radio ...i\.ssociation, Inc., Providence, however, and the flames were subdued with the R. I. aid of a bucket of sand. W6WII stood by during The Ridgewood Radio Club, Ridgewood, New the "emergency" and the contact was eventually Jersey Santa Clara County Amateur Radio Association, resumed. Who says dreams don't enmc true'? Inc.~ San J·ose, Calif. Ranta Monica Mike & Key Club, Inc., Venice, Calif. On February 13, 1938, W0YBD worked Somerset Hills Radio Club, Summit, N. J. South Lyme Beer, Chowder and Propagation So- W9KBD on 160-meter 'phone. W9KBD made ciety, South Lyme. Conn. out a qSL card to W0YBD but neglected to mail Htarved Rock Radio Club, Utica, Illinois it. He did so on February 3, 1948, appending a T-9 Radio Club, Danvers, Mass. note which said, "Forgot to mail this card ten Umon County Amateur Radio Asaociation, Ine,, Blizabeth, N. J. years ago." The QSL arrived at W0YBD Febru Valley Radio Society, North Hollywood, Calif. ~y lat,h, ten years to the day from the time the Walla Walla Radio Amateur Club, Walla Walla, contact was made! Wash. Westfield Amateur Radio & Emergency Communi cations Assn., Westfield, Mass. Coincidence: W5HOX sent radiograms to Winston-Salem Amateur Radio Club, Inc., Winston WlLRZ asking for a schedule and leaving the Salem, N. C. choice of band and frequency to the latter. He York Road Radio Club, Elkins Park, Pa. also sent a similar message to W6VUO. Replies June 1948 73 MEET THE SCMs F.M.T. RESULTS Walter L. Glover, WlVB, Connecticut's Continued interest in the ARRL Frequency SCM, has enjoyed amateur radio since 1914, al Measuring Tests is indica.tive of the pride taken though his license was not obtained until 1925. by many amateurs in their ability to measure WlVB's operating position is situated on the radio frequencies with accuracy. :The First 1947 first floor of his house, while finals and power ARRL Frequency Measuring Test, one of two supplies are kept in the basement. 'fransmitting such competitions open each year to both ARRL line-up includes the following: 6SK7-6J5-6V6-807 Official Observer appointees and other amateurs, erystal-VFO exciter followed by separate ampli brought entries from 192 participants. Measure fiers, an 810 running 550 watts on 3.5 Mc., a ments were submitted by 75 OOs and 117 non pair of 813s at 650 watts on 7 Mc. and 600 watts appointees. to 813s on 14 Mc. Receiver: BG"779A Super-Pro. Individual ratings, based on comparison of Antennas in regular use: three half-wave doub rnt'-asurements of the frequencies used by WlAW lets, coaxial-cable-fed, for each band used. during the special FMT transmissions on January In August, 1940, 23rd with those made by a commercial frequency Glover was awarded a measuring laboratory', have been sent to each :35-w.p.m. Code Profi participant. The following frequencies were used ciency Certificate and byWlAW: has since increased his speed to 45 w.p.m. He :3755.479 3643.673 has held an A-1 Oper 14.302.080 7138.938 ator Certificate since 28005.12 14399.074 before the war. Al 28030.08 though interested The leader in each group has received a G. E. mainly in traffic han Type 8H58 Select-O-Switch clock in recognition dling, he is a versatile of his efforts. Prize winner in the 00 category amateur and has par was T .•T. Lydon, W2ANW; in the non-OO class, ticipated in SS and Lloyd W. Root, W8HB. CD Contests, was RM and assistant SOM, which The standings of other leaders in the FMT are posts he relinquished upon his election as SOM, tabulated below. No entry consisting of a single and now is ORS and assistant director. The measurement was considered eligible in the prize Candlewood Amateur Radio Association of Dan competition. Except where indicated, entries bury claims him as a member. included two or more measurements. From 1917 to 1918 and again from 1919 to 1923 he held positions as radio operator, taking LEADERS time out in between to serve in the Nayy. A civic-minded citizen, Walt takes a keen Pam/ Paru/ interest in town government and affairs, is chair Obseroer• Million Non-Obseroer• Million W2ANW...... 1.1 W8HB...... 1.8 man of the Board of Fire Commissioners, chief W9CIB...... 1.7 W2MRG .. ,...... 2.1 of the Newtown Fire Department, and a member W8WWL...... 1.9 W2RYT .. , :.i.2 of the Board of Finance. His favorite sport is W2BF...... 3.3 W2CVV...... 3.8 W7CQE...... 3.9 WSGXI...... 4.9 bowling. At present he conducts his own electri W5AIR...... 7.2 W6CQI...... 5.9 oal contracting business. 'WlLQQ,, ...... ,. 8.8 W9EG...... 6.7 W3VNE...... 9.7 WIMUN...... 7.0 BRIEF W9KA...... 9.7 W!KSD...... 7.9 The Fort Wayne Ra.dio Club is sponsoring a WlDWO. . .. 11.7 VE3PO...... 8.1 W3ASW...... 11.7 W7GPP... 8.-l "WFW" contest, open to all amateurs. Object, of WlLVQ . . 11.8 W7BQS...... 9.2 the competition is to work as many stations as WlPXH ..•...... 12.3 WlBGW ...... lO.l possible in Fort Wayne, Indiana. Prizes will be WOOTR.... 13.4. W2IDZ...... 10.7 VElQU ...... 14.7 W2WFU ...... l.0.7 awarded to the amateurs who have worked the W6DFO ..... ,.. ... 16.1 W4IIY...... 11.9 greatest number of stations by a date to be an W9SRN ...... 18.2 W9JNU .... , .. , . . lUI nounced later. The contest is of a continuing na, W2NCY ...... 19.2 WlLKF...... 12.2 ture and does not close on the awarding of prizes. WlVW ..... , ..... 19.8 W9VDB ... ,...... 12.8 W8LEC... 20.1 WlBB ... , ...... 13.6 A certificate will be awarded to each amateur W6GTE ...... 21.1 W5HOU...... 13.6 who contacts 50 Fort Wayne hams and endors1r W6IWU ...... 21.6 WlAYO ...... 13.7 ment stickers will be awarded for each additional VE6HM ...... 22.2 W9PVA, ...... , 13.8 W8SDD ...... 24.1 W9BOR...... 13.9 ten stations worked. QSL verification of contacts WSJRG...... 25.5 W3MBF ...... 14.8 is preferred, but the station log will be accepted W3MCG ...... 14.8 in lieu of QSL cards. At IP..ast 5 contacts of the 50 must be on c.w. and 5 on 'phone. Further details The following ratings are based on a single measu.rement: O°'9-WION 4.9, W3EYX 5.6, W6GC 10.13, W2WI may be obtained from Harold Norton, jr., .!6.7, W4IYC 20.0. Non-OOs-W2PAH 0.2689, VE2JN W9PRO, 1723 Sherman St., Fort Wayne, Indiana. 11.3, WlAPK 12.4, WlAJQ 14.5, WlQGT 14.5. 74 QST for ELECTION NOTICE A.R.R.L. ACTIVITIES CALENDAR (To all ARRL Member• residing in the Section, listed bel.ow:) You are hereby notified that an election for Section Com June 12th-13th: ARRL Field Day munications Manager is about to be held in your respective June 21st: CP Qualifying Run Sections. This notice supereedes previous notices. ,July 14th: CP Qualifying Run Nominating petitions are solicited. The signatures of five July 24th-25th: CD QSO Party or more ARRL full members of the Section concerned, in Aug. 19th: CP Qualifying Run good standing, a.re required on each petition. No member shall sign more than one petition. Sept. 14th: CP Qualifying Run Each candidate for Section Communications Manager Sept. 25th: V.11.F. Party must have been a licensed amateur for at least two years Oct. 16th-17th: Simulated-Emergency and similarly a full member of the League for"at least one 'fest continuous year immediately prior to his nomination. Oct.18th: CP Qualifying Run Petitions must be in West Hartford, Conn., on or before Oct. 23rd-24th: CD QSO Party noon on the closing dates specified. In oases where no valid 13th-14th: Sweepstakes Contest nominating petitions were received in response to previous Nov. notices, the closing dates are set ahead to the dates given ('phone) herewith. The complete name, address, and station call of Nov. 17th: CP Qualifying Run the candidate should be included with the petition. It is Nov. 20th-21st: Sweepstakes Contest advisable that eight or t'-ln full-member signatures be ob (c.w.) tained, since on checking names against Headquarters files, with no time to return invalid petitions for additions, a petition may be found invalid by reason of expiring mem Jan. 1st-Dee. 31st: Most-States V.11.F. lilerships, individual signers uncertain or ignorant of their Contest membenihip status, etc. FiJ,"St Saturday night each month: ARRL The following nomination form is suggested: Officials Nite (Get-together for SCMs, RMs, SECs, ECs, PAMs, liq. Staff, Di Communications Manager, ARRL (Place and date) rectors,, Alt. and Asst. Dirs.) 38 La Salle Road, West Hartford, Conn. We, the undersigned full members of the ...... • • • • • • • • • • . • . • ...... • ARRL Section of the ...... Division, hereby nominate ...... as candidate for Section Commanications Manager for this CODE-PROFICIENCY PROGRAM Section for the next two-year term of office. Have you received an ARRL Code Proficiency Elections will take place immediately after the closing Certificate yet? Once each month special trans dates specified for receipt of nominating petitiona. The missions are made to enable you to qualify for ballots mailed from Headquarters to full members will list the award. The next such qualifying run will be in alphabetical sequence the names of all eligible candidatea. You are urged to take the initiative and file nominatins,: made on June 21st at 10:00 P.M. EST. Identical petitions immediately. This is your opportunity to put the texts will be sent simultaneously by automatic man of your choice in office. transmitters from WlAW, W60WP and W0CO. - P. Fl. Handy, Communications Manager Frequencies of transmission from WlAW will be Pr1Bent 3555, 7215, 14,150, 28,060, 52,000 and 146,000 Section (Jlosinq Daf! SOM T,rmElllh kc., from W60WP 7248 kc., from W0CO 3534, Arkansas June 1, 1948 Marshall Riggs Juno 14, 1948 North Carolina June 1, 1948 W. J. Wortman June 14, 1948 7053 and 14,040 kc. Send your copies of the Virginia June 1, 1948 Walter R. Bullington J1me 14, 1948 qualifying run to ARRL for grading, stating Nevada June 1, 1948 N. Arthur Sowle June 15, 1948 the call of the statfom you copied. If you qualify, Northern June 1, 1948 John J. Vitale June 17, 1948 you will receive a . certificate. If your initial New Jersey Idaho ,Tune 1, 1918 Alan K. Ross June 17, 1948 qualification is for a speed below 35 w.p.m., Manitoba* June 15, 1948 A. W. Morley Resigned you may try .later for endorsement stickers Ontario* Jun~ 15, 1948 David S. Hutchinson May 1, 1048 indicating progress above t.he first certified speed. British June 15, 1948 W. W. Storey May 1, 1948 Columbia* Code-practice transmissions are made , from Colorado June 15, 1948 Glen Bond April 17. 1048 WlAW each evening, Monday through Fpday, Philippines July 30, 1948 George L. Rickard Oct. 15, 1938 at 10:00 P.M. EST. Take advantage of 'these Ohio Jtily 30, 1948 William D. Montgomery Aug. 17, 1948 transmissions to increase your code proficiency. * 1n Canaiian Sections nominating petitiORs for Section Managers References to texts used on several of the practice must be addressed to Canadian General Manager Alex Reid, 169 transmission& are given below. These make it Logan Ave., St. Lambert, Quebr c. To be valid such petitions must be possible to check your own copy. filed with him on or before the closing dates nam€d. Date: Subject of Practice Text from April QST: ELECTION RESULTS June 2nd: Seloctable Sinu!e-Sideband Reception Simplified, Valid petitions nominating a single candidate as Section p. 11. Manager were filed in a number of Sections, as provided in June 4th: An Oscillator for the 1S15-Mo. Band, p. 16 our Constitution and By-Laws, electing the following; offi June 7th: Selectivit11 in S.S.S.O. Reception, p. 19 cials, the term of office starting on the date given. June 10th: Better Reception for It-Meter Mobile, p. 23 June 15th: .1n Automatic Keuino Monitor, p. 27 Tennessee Ward Buhrman, W4QT Mar. 15, 1948 .June 17th: A Balanced-Modulator N.F.M. Exciter, p, 83 fa the Georgia Section of the Southeastern Division, Mr. June 21st: Qualifying Run, 10:00 P.M. EST Clay Griffin, WIDXI, and Mr. Warren S. Pope, W4HDO, June 23rd: Self-Filtered Peak Clipping, p. 36 were nominated. Mr. Griffin received 88 votes and Mr. ,Tune 25th: Oompact.!10-WsU Rig for 60 Mc., p. 44 Pope received 86 votes. Mr. Griffin's term of office began June 29th: Notu on Pw,h-Pull Triodea, p. 55 March 8, 1948. June 1948 76 countries with that famous 807 •. EFZ has a St5-er using BC-453. JZY is building a 144-Mc. converter. CJS is hack • All operating amateurs are invited to on 7 Mc. after 14 years off, and is getting out fine using an indoor antenna. IZL is calibrating a new frequency meter, report to the SCM on the first of each and recently worked 15 new countries on 28-Mc, 'phone. month. eo,·ering station activities for the DVO is rebuilding his rig for 400 watts. LYM has a new 200- preceding month. Radio Club news is watt rig on 28-Mc. 'phone that works very well. KFO is on 144 Mc. CDQ is using indoor autenna on 7 Mc. and gets out also desired by SCMs for inclusion in OK. Traffic: W2NDL/3 339, W3ECP 324, AKB 133, BWT these columns. The addresses of all 55, QL 36, MJQ 33, AKR 27, JZY 22, CJS 6, AQV 4, JVG 3. SCMs will be found on page 6. SOUTHERN NEW JERSI>JY-SCM. G. W. (Bill) Tunnell, W2OXX - We hear from GCU after a long si lence. He has just finished his new antenna. ORS is listening on the 420-Mc. band but results are poor. BAY will spend the coming months working on his boat. CFB soon will be ATLANTIC DIVISION active from Toms River. RG reports favorable response to -.:;,ASTERN PENNSYLVANIA -··SCM, Jerry Mathis, automatic roll call for the a700-kc. net.. PAU, RXZ, and J.'..I W3BES - Report from the Lancaster Radio Transmit QED are active in the new 144-1\fo. "X" Net operating from ting Society: DYT iH erecting a new 80-ft. tower. QV will New York to Washington, D. C. QUH is mastering his radio attend its third annual dinner meeting. NOK is graduating course and is therefore more active. Congratulations to ZI from 144 to .1 and 3.5 Mc. New ollicers: KIE, pres.; NOY. and the "committee" for another F'B Old Timers' Nite. vice-pres.; OY, secy.; DYT, treas.; NOK and LN, board of · SUG has been a receutAltemate NCSfortheSNJ-ORS Net. directors. MAC has started a flood network on 28 Mc. for RPH is having B.C.I. troubles. SAK is still slui,:ging hard the Lehigh Valley section. They are receiving excellent press at emergency work. llAZ reports that the Delaware Valley publicity, MAC is most interested in working with the W2 Club is spoi;isoring two contests for it~ members, one for the stations around Trenton. Give him your support, you first three SWLs hearing all stat<'.s and the other for the first fellows in his territory. He also is active on 144 Mc. and is t,hree amateurs working all states, both requiring confirma trying to get through to Philadelphia. In 15 months MAC tion. The recently-elected officers for this club are: SMP, has worked 78 countries on 28 Mc. with only 55 watts. pres.j UPS, vice-µres.; HAZ, secy.; and H. L. Yoder, treas.; Quite a stunt, for he cannot see. The Delco Club has its whose recent death is mourned by all. Look for OSB/9 on •tation, DUU, on with 250 watts on3.5-Mc. c.w. The Harris 3.5- and 7-Mc. c.w. RDK reports by letter that an auto burg Club is organizing an emergency net with fixed porta mobile smashed his beam in a freak front yard accident. ble and mobile equipment. The E. Pa. net wants more The SJRA has guest speakern planned for the next three traffic to keep the net hot. Ql>JW reports KLZ. KFU, LCK. months. PWM, ex-3DAJ, is active a11:ain on 14 Mc. Traffic: LKL, NIU, <.iGE, and himself very active on 144 Mc. LAK W2RPH 266, SUG 79. ZI 53, QUH 42, PAU 19, RG 18, is activities manager for the Susquehanna Valley Amateur BAY 14, CFB 14, BE! 11, GCU 7, ORS 7. Radio Club. Members in that area, please get your activity WESTERN NEW YORK - SCM, Harding A. Clark, reports to him right after the first of each'month since th'e W2PGT-SEC: SJV. RM: FCG. New appointments: SCM must file with ARRL on the 7th. DZ received a Trunk ORS: WFU. RM: FCG. On March 26th the Triple Cities Line Certificate. MPY has his 28-Mc. mobile working fine. 144-Mc. net held a simulated emergency drill with the ELI and EU have new QTHa. MET is back on his 00 job NYC/LI 144-Mc. net with NYS and NYC/LI 3.5-Mc. nets again. CAU snagged four out-of-band stations this month. as the relay link. There was a total of 24 stations partici AQN has 100 watts on 144 Mc. Members of the Frankford pating and the test ran off without difficulty. Congratula Radio Club are trying to keep the high end of the 50-Mc. tions on a job well done. Plans are now under way to con hand occupied and now represent about 90 per cent of the duct similar tests with other 144-Mc. nets throughout the activity in the area. They have been putting out DX broad section. Will you be ready when the time nomes for your casts to eirnourage listening by stJttions not ordinarily drill? The following ECs have been appointed: '\VQI for attracted to v.h.f. but would be interested in gleaning the Oneida County; DV for Washington, Warren, and Sara latest and hottest DX information from the inost active toga Counties; QJT for Tompkins County; and SXR for DX group in the country. The FRC feels that similar action Otsego County. New officers of RAWNY are: TBD, pre,11.; by the various radio clubs would bring enough actiYit.y to QWS, vice-pres.: UJR, secy.; UYG, rec. secy,; AFY, treas. the 50-Mc. hand, especiallv the 54.-Mc. end, to assure our FCC Engineer Rockman was guest at RAWNY meeting retaining the band. The wie of 50 Mc. takes a load off the and QHF explained s.s.s.c. transmission and reception. crowded DX bands and to date the sixteen active F'RC QHF also spoke 911 tele,ision trans_mitt-ers and re9eivers a.t members have not had a t.v.i. complaint. Traffic: (F'eb.) .B:BT meeting. ORG, UZS, VZX, WQR, RXM, RTA, and W~OML 20. (Mar.J WaVMF 150, KFA 148, EU 86, OPZ keep Buffalo on the 7-Mc. map. WME has reached the QEW 60, QV 47, DZ 40, AQN 37, OML 10, CAU 5, ID 5, i,entury mark on 28-Mc. 'phone. UHJ will be on with s.,u.c. NNV3. rig from new location. Oneida County 144~1\,Ic. net now MARYLAND-DELAWARE-DISTRICT OF COLUM includes WQI, VUF. SOD, QFG, WHN. and TRG. More BIA- SCJ\I, Eppa W. Dame, W3BWT -The Baltimore members are wanted. Drills are held each Sunday at g P,M. Amateur Radio Communications Society had two splendid VUF is the first to successfully convert t:lUR-522. The Utica speakers at its March 15th meeting. John Reinartz, 3RB, Amateur Radio Club raffled a.m.-1.m. console to raise funds spoke on "Simplified F. M., 11 a.nd our .Atlantic Division for treasury. QNAand TJB are on 50 Mc. YDU is new ham Director, "Brad" Martin, 3QV, talked on ARRL activities. in Niagara F'alls. QHH has retired from 3.5-Mc. DX for Hoth talks were extremely interesting. A large group of the season and wound up with 36 countries u.sing 10 to l 7 hams from Baltimore were in attendance, plus a group from watts. What would he do with a kw.? AOR ga>·P. ;J •.5-Mc. Washington. At its first March meeting the Washington DX" whirl and landed G2JT, ON4AU. and 1"A8BG. HZP Radio Club devoted most of the evening to a discWlSion of a is newcomer to Hornell. The Oneida Club_ had good at new constitution, submitted by !,he constitution committee, tendance and program followed by a hang-up feed at its ECP, FMC, and MAX. Talks on their Hawaiian trip by recent open house. 8vracuse Radio Club now meets at its MHW and MSK were enjoyed by the membership. At tile new quarters in WF.BL studio. Meetings are held second oer;ond March meeting, the Club visited the television stu and fourth Thursday of ea.ch month. Everybody in the area dios of the DuMont Company, WTTG. The Capitol Subur is cordially invited to attend. We are all glad to hear that ban Radio Club has a net on 29,009 kc. OFS is newly RUF had a speedy re.(\Overy after recent operation and is licensed station at College Park, Md. MJQ is having back on the air. Traffic: W2NAI 354, PGT 343, BLO 146, "antenna-landlord" troubles. CJT has been appointed ~CG 116, )VFU 981 SJV 94, VIQ Sn, SXR 58, \VOE 52, ORS. JVG is on 3.5 Mc. and is building equipment for 420 C,WY 42, SZK 40, RUF 38, UYO 36, AOR 24, QHH 12, Mc. MLJ reports from England and is spending a great deal QNA 10. of time visiting British hams. He has also been on 14-Mc. \Vl>JSTERN Pl>JNNSYLVANB. - SCM, l>Jrnest .r. 'phone at (J.5GK. KHM has a new h.f. 28-14-Mc. converter. Hlinsky, W3KWL--EC: UST. RMs: TOJ, MJK, and LCB, a new ham in Greenbelt, is on 7 Mc. NOL is building NUG. PAMs: AER and RAT. In Altoona the 144-Mo. boys a mobile rig for 28 Mc. FYB is working nights, but gets on are going strong with MLU, RFM, MYN, and LQD doing with his mobile rig while traveling to and from work. the honors. TXQ is using 14-Mc. folded dipole. LJQ built MCA has a new Collins VFO. MJQ is putting out a nice• a 28- and 50-Mc. converter and is looking for 50-Mc. con •ignal on 3.5 Mc. using a ten-foot indoor antenna. A~V has tacts. The Horseshoe Radio Club presents code classes for moved to his summer operating position "Studio A.' AHQ beginners. LJQ is eJiting club paper. UVD reports the fol is rebuilding, but is on with temporary rig. ECP is on 28- lowing; 'WESCO gang wants t,o become alliliated with Mc. 'phone; he also makes BPL this month. 2NDL/3 had ARRL. A theory group for Class A and B is in the making. highest traffic total in the section. LVJ has worked 109 (Oontinued on paae 78) ~ C 76 ~======~ ( Number one hundred seventy-one of a series J ~==~ \!\TE HA VE read with interest the various articles on amateur s.s.s.c. and probably you have too. One thing that quickly becomes obvious is that the trans mitter must be of simple straight forward design to be practical for the uninitiated. This is particularly true due to the newness of techniques as well as newness of the idea to many of us. The classical s.s.s.c. transmitter is one having a first modulator operating at a low frequency so that the unwanted side band can be eliminated by a good filter. The carrier is supressed by the modulator with this system. The first modulating and filtering operation in the transmitter is prob ably the most difficult. With this thought in mind National has made available the type F-22 side-band filter so that this difficult problem can be solved more easily. A low center frequency was picked to assure that good filtering would be obtained. If 200 cycles is considered to be the lowest audio frequency to be used, this filter should attenuate signals that are 400 cycles or more outside of its pass band by at least 50 db. to eliminate the unwanted side band. This figure is suggested on the basis of a high standard of performance and can be obtained with the F-22 side-band filter. Due to the "universal" nature of selectivity curves for either i.f. trans formers or filter sections, the slope of the attenuation characteristic at the side of the pass band in db. per kilocycle becomes greater as the center frequency is lowered if the same Q,, etc. is maintained. This is why it is necessary to go to a low frequency in order to effectively eliminate one of two frequencies which are separated by only 400 cycles as is the case at the output of the first modulator in the s.s.s.c. transmitter. It is interesting to note that the percentage difference between the closest frequencies that must be separated may be less at the output of the second modulator than at the output of the first modulator in typical arrange ments. However, at the second modulator output, it is usually not a diffi cult filtering operation becai;ise the required coil Q is relatively easy to obtain at these higher frequencies. If this were not the case, a second special filter would be necessary. Similarly, the third modulator output filtering does not require a special filter if 75 and 20 meter phone operation only is contemplated. Give s.s.s.c. a try and let us know how you make out. We believe it holds a great future for amateur radio. RALPH HAWKINS, W10EX ADVERTISEMENT 77 LEJ is club secretary. OFJ is a new station. OMG has an WNM. QIN, 3656 kc. INP, 3905 kc. WNM asks that all RME-69' receiver. FIR finds 14-Mc. 'phone too towcli so is holders of EE and AEC certificates or oa.rda check expiration tryinz 7-Mc. c.w. VNE was buay as 00 in DX Contest. date and if necessary send them in for endorsement. BCJ KT.A. report.. FB results on 14-Mc. n.f.m. LIM worked his has a new final UBing 813s with 900 watts inP,ut. J!'SG has first Jin 25 yearn of radio. AER is knocking 'em off with a been endorsed as SCM by the Indianapolis Club. IUM, of VR and ZC contact. LGM schedules LF2K ea.ch Sunday. Auburn, is new OBS and sends officia.l bulletins dail'f on GJY did a nice job running W. Pa. ORS Net. MHE was 29,300 kc. at 6:00 P.ll. CST. HNS, new president o the busy as 00; he claims 47 c.w. violators. Up north LOD is Indianapolis Club, baa worked 39 states in four montba and keeping tabs on VE 'phone QRM on 3750 ko. LQQ is faith ,5 VE districts using a 6L6 on 7-Mc. o.w. UDD spoke on fully holding the ORS Net. MOT says there a.re two SCR- "Grid Dip Oscillators" before the Fort Wayne Club on 5228 in town on 144 Mc. Congrats to MOT on the nice March 19th. DKV is Northeastern Indiana's newest and ARRL Party score. The Upper Ohio Valley Emergency youngest 8.Il)8,teur. Pete is 14 years old and has a Class B WP,ather Net is well organized with the following, in addi ticket. His equipment is an 840A and a BC-474.A.. Using a tion to PY a.a NCS and MPO as ANCS, reporting ea.ch half-wave long wire he has worked ten states in six districts. Sunday at 9 A.M. on 3965 kc.: CA V, HUL, RMM, BOZ, JW, KMY is at school in Milwaukee. CFI has a BC-696A on VRZ, LlK, PFW, UG, IB, SGA SPHY, SUTO, SMIS, a.nd 3..85 Mc. and worked an XE. Look .for an article~ John T. SJIL. In Erie QIU has given up 144 Mc. for television. VHP Frye, EGV, soon to appear in "Today's Woman.• QIB, of a.nd LJF had beams down in storms. In Mercer County the Indianapolis, has 109 countries and is closely followed by 144-Mc. craze is on. You 144-Mc. DX hounds ca.n alws.ys CKP of the same town. BZB has 79 countries and 31 zones. get a. ~'O a.ny night with these valley stations on. LNA GXB is on 14-Mc. 'phone after two yea.rs of building. DPL, and M W a.re heard nightly on 144 Mc. The Mercer County at Ease, called a trucking concern for a truck and trailer to Radio lub will become an ARRL mernber club. AAT is haul over 3000 amplifiers to the N. Y. area.. When the truck knocking off nice DX on 27-Mc. 'phone. ODB, with 30 arrived he was aurpriaed to find the driver was GGP. Capt. wa.tta and in two montba, baa worked 31 states and Cuba. Robert Smith, XARC. in Trieste, is on 28,293 kc. and look Keep your eyes open for the Brass Pounders a.nd Modula.tors ing for contacts with Indianapolis 28-Mc. boys. HAR Club of Pittsburicli summer ha.mfeast, same time and place worked him using 30 watts. GPA is working for Allen B. aslastyea.r. 'l'ra.llic: (Jan.) W3KKA 71. U'eb.) W3KKA 114. DuMont Laboratories at Clifton, N. J. BKJ has a 40-ft. (Ma.r.l W3YA 197, KKA 135, GJY 84 Mmll 38, KWL 36, windmill. He still is complaining abont small a.mount of NCJ 34, NT 31, AER 30, LGM 12, I.OD 12, LWN 9, LQQ publicity received by the 'phone net. The IRRC met in 5,MOT2. Indianapolis Apr. 18th. Watch for announcement of an Indiana get-together this summer. This is 73 for your present CENTRAL DIVISION SCM. Next time it will be just plain old SWH who will ssy LLINOIS - SCM, Wesley E. Marriner, W9AND - 7~~~~~'li!! ~~ri~P!:Y:'ot~;/~~':kantf.!:o~~~ I The KRC Club was organized at DeKalb with SIU, ~9TT 139, NH 109, BCJ 88, YB 35, BKJ 31, UKT 18, pres.; A TW, vice-pres.; 'rwM, secy,; WED, treas. Meetings KTX 17i~Q 16, EGV 10, DOK 8, RE 6, HZB 4, RJU 4, are held the second Monday of each month. DAX and DDlu~L , KZO demonstrated crystal grinding at a recent meeting of WISCONSIN - SOM. Reno W. Goetsch, W9RQM - the club. UPW is working on a higher code speed. LBL It's a date - Sept. 4J 5, 6, - the National ARRL Conven joined the Daylite Net. Starved Rock Radio Club news: tion in Milwaukee. 1t will be worth your while to seeure ZEN is st~ing with a. pair of 813s in a new rig. NIU is advance re.glstration. GPI is general chairman. Central on 3.85-Mc. phone with 7 watts. NOO plans a comeback Wisconsin Amateur Radio Club report is furnished by TOB, a.nd has purchased a receiver and parts for rig. IDA ia look secy. Newly licensed at ·wisconsin Rapids is DEB, age 15, !~K for last few states for 14-Mc. phone WAS. CDG, ATA, now active on 3.5--Mc. c.w. ZSY has the DX bug. Central YBY, and JAU plan publicity for ha.m radio ·in Streator Wisconsin Club has 28-Mc. emergency net, which meets paper. A hamfest baa been planned for June 6th. 2STX/9 ea.ch Tuesday at 10 P.M. Ra.cine Megacycle Club and Wis described operations at Bakelite plant at Ottawa. ACJ consin Valley Radio ABSn. are in the midst of Field D~ reports the following Illinois Valle)' Radio Assn. news: OBB preparations. BQP and CAI are new calls at Racine. PFH is rebuilding. ZHB, JVC, and PBY are on 50 Mc. with baa a BC-453 working as a Q5-er. RPS and RMF increased ZHB working out 200 miles. Field Day preparations were power to 300 watts. VWQ is looking for Idaho and Nevada made and members a.re eager to participate. The Club Net for 7-Me. WAS. KZZ and BVG are nsing BC..453a as Q5--ers. operates Monday, 8 P.M., on 28-Mc. 'phone and Sunday, 9 P.M., forc.w, IQC baa remodeled intoaclass,yshack. OLM, ~~alma:J_M~.t~bl!e t~in::r:- ~o:~:.'1.Jj'jtJ°'i:.°1,!~! the 3.85-Mc. engineer, is to go up for his Claas A ticket soon. reinstated as Ra.cine Megacycle Club call. Club activity WDD baa a new Silver 701 rig and 28-Mc. dipole. TAL has plans include a 144--Mc. contest, emergency net, WAC and an HT-18 driving an HT-9 and has 55 countries postwar on WAS contests, and a awe!! educational program. An out 14 Mc. LQP is working nights and lookin,r for daytime standing job as 00 is being done by CIR and he had an traffic nets. BRX has new frequency standard-a.nd will have accuracy of .00017 per cent in the last FMT. QGQ is inter radar antenna. rotator for 14-, 28-, and 50-Mc. beams. ASN eated in EC activity. AFT is OPS and OES. lOiJr has 44 has started in traffic work and is doing quite well. NN is on countries, SEC LZU is busy co/lrdinating emergency plan 7 Mc. nightly looking for A-1 Operator Club material. PEK ning_ and activity in the section and will be on the BEN is new EC for DeWitt Countv. Wind took both poles at regularl:v. RUF, Milwaukee EC, has 22 members active on IFM. CTZ is new ORS. BUK is buay organizing Radio 144-Mc: net. CFT and Wisconsin Valley Radio Assn. are Emergency Assn., Red Cross set-up at Evanston, with B UK, providing super-service from the W9 QSL Bureau. Director pres.; TO, comm. mgr.; UIN, vice-pres.; PSR, secy.Close ARE moved to R. 3, Marshfield, where he has a new antenna. cooperation with State traffic nets niJilitlv is planned. A farm. LFK added Q5-er to receiver. DXV completed new teletype connection is maintained witn Chicago. LIN has ha.lf-kw._p.p_. 813 rig. YCV rebuilt to 250-watt p,p. final. 210 watts to a pair of 811s on 3735 kc. He will accept for Traffic: W9LFK 223, ESJ 113, IQW 112, UFX 78, SZL 55, delivery traffic for Waukegan, North Chicago, or Great DXV 33, PIG 29 srz 24. cwz 23, MUM 23, RQM 20, Lakes Naval Training Center. GMV reports general atti CBE 18, LKL 18, bAE 12, YCV/9 8, CIR 7, QJW 5. LZU 2. tude on 00 work very good. S..XL baa biggest total since starting traffic. KA took part in the last Frequency Measur DAKOTA DIVISION ing Test and his measurements were the best he ever made. The following news came from the Society Radio Operators: ORTH ,DAKOTA-SOM, Paul M. BoBSoletti, The club house is at 4222 West Foster Ave., Chicago. Meet N WSGZD - ZXT and HIV are new ca!Js in :Fon:. RBS ings are held the first and third Wednesdays of ea.ch month. moved to Billings. ZRT donated. hia ranch a.nd 160 acres to New officers are: TXZ, pres.; SOZ, vice-pres.; BPM, secy.; Cendak Club for a club house. Doc has been appointed AJC, treas.; WFX; chaplain; GAI, ma.rahall. GAI also is ABSlstant Director. WFO has new 3.85-Mo. Zepp. VKB ia editor o£ the SRO News Letter. The club has purchased a. new call at Grafton and AZV new station in Bismarck. TSN, 167BY c.w. transmitter. The SRO picnic will be held a.t Dakota Division Director, and a hip; turnout of eastern Orcha.rd Grove on J ul;ir 25th. The price - one_ greenback. North Dakota ha.ms attended Fon: Club meeting. HGK SRO roster includes: RLZ, IR, ASI, SWO, GAI, TXZ, moved to Park River a.nd schedules GHN. MKD alleges RMO, SOZ. BZT, BP¥, RLM, GUH, QGZ, BL!, TRZ, he bu received an SWL ca.rd from England reporting having EEH, KQT, LXD, Q•.~~ IVB, QWP, BOM, LAB, AJC, heard him on 122.1 Mc. while he was running only ½-watt LSQ, RHN_, DOX, H_;u,;, ES, E~J, QVO, LOV, HTQ, iaput. AZN is the first ham a.t Garrison Dam. GJJ has new KTL, QBJ, WFX, CGX, and 7RIA 9. CIA has FB _postwar FB 28-Mc. mobile rig. Bill, Aneta, ia back on the air. CTS DX total o.f 153 countries with 6 watts. The Amateur bought RBS radio service. GWU is back on from Forx. Radio Club of the U. of Ill. and the Illinois Valley Radio VAZ is rebuilding. 3.5-Mc. o. w. souncl!, good with all you Asen. recently were a.ffiliated with ARRL. The Starved boys coming back on the band for neighborly QSOs. Traffic: Rock Radio Club hamfest will be held June 6th at Camp wassw 128, GZD 24, BCH 11. Ki-Sha.u-Wa.u. The dub is erec~ two 90-ft. towers at the SOUTH DAKOTA-SOM, J. S. Foasberg, WSNGM club house. BIN has new Class A ticket and worked KS4AI SRX reports that the Yankton gang has several new pros on 3.5 Mc. Some Illinois DX Contest Scores are: FJB pects now up for exams. SRX, on 14 and 7 Mo. with 500 12..3~000, AEH 113 832, LM 108,486, ERU 82,000, GA 73,000, watts to an 810, has worked 61 countries since last fa!L ION Ul'IG 72,00Qi NI1 66,000. Traffic: W9EVJ 635, VOA 332, is on 14-Mc. 'phone. HJV is on 14-Mc. 'phone and baa a KQL 312, SxZ 273, CTZ 145, PEK 139, SXL 134, ZPC 59, new YL ha.rmonlc. SRX, ELV, and ION are installing a new 1'.lEM 37, FKI 23, MRQ 21, NN 16, RSM 13, BIN 6, IFM 5-kw. transmitter at WNAX. RNN plans to have an AP 6, ASN 5, BUK 2, EBX 2, 'rAL 2. reporter on the 3.85-Mc. net to get information to write a. INDIANA- SCM, Ted K. Clifton, W9SWH - SEC: (Continu_ed on page 80) · · 78 ~----•# ---#• --~#: --~-----l--- - .. -•-----•------:------,------,_, ____ _ -,-\------~----___ , __ _ ----', ----'~ Tens of thousands of PR Precision brated within .005 per cent of specified CRYSTALS in commercial service the frequency ••• contamination and mois- world over are eloquent evidence that ture-proof ••• weight less than ¾ ounce. PRs STAY PUT! In aircraft, in the ma- Power output is exceptional, both for rine, in broadcast and point-to-point, in fundamental and harmonic oscillators. police and military installations ••• in Since 1934 PR has become a standard fact, wherever frequencies MUST he of excellence for crystal controls ••• in in channel .•. you will find PRs on the all fields - commercial, amateur and job. PRs for commercial service are industrial. It's no wonder that amateurs precision made •.• low drift cut for the prefer PRs in their rigs at all frequen- utmost in stability ••• with temperature cies. Use PR and KNOW WHERE YOU coefficient less than 2 cycles per meg- AREi-Petersen Radio Company, Inc., acycle per degree Centigrade ••• cali- 2800 W. Broadway, Council Bluffs, Ia. ~ Harmonic oscillator. Ideal fol' . ••~" 10 METERS ;;~,i.algfil ~h~¥fv~;~_mfi:~~~y°~;; 111..T.J without !amage in our special cir- PR Type Z-5. cuit •.•....•••.•....•.. $5.oo ------HaTmonie oscillator. Low dri.ft. 20 METERS g:f.~ g{'.,~~tl: m'i:'bn J;,e~eg;:tpJE _!!.I.Y!~!":!: __ ~f!t~~:~ ~~i~~~~:;Ji.. Rugged. low drift fundamental Os• 40 & 80 METERS cillators.. High a~tivity and power output with maxunum crystal cur- PR Type Z-Z. rents. Accurate calibration .. $2.75 79 feature story. QVY reports that MNI, rnariue mobile and :3.5 Mc. DIY has Marine r:ig. LVW operates 28-Mc aboard the SS C,4ar Breaks, looks forward to his return to mobile. VT discoursed on grid dip meter before Memphis South Dakota. Rapid City's youngest ham is GFG, who is dub. FCF has smooth power control from 100 to 1000 18 years old. New statious on from Rapid Citv are GOW, watts. AA W is erecting new antennas. AFR is skeptical of with a. new kw. rig; YOB, on 28-Mc. '\>hone; arid QHX aud nnderground antennas. DDF, new QSL Manager, wants SKM on 28-Mc. 'phone. GLA is SEC and drills are being envel~pes (with stamps!) from DX gang. He would like held in the. H"tlls. GCP, the RM, is doing yoernan duty'. t-o deliver several thousand cards, some dating back to 1935. HDO is OPS. YPC has hls Class A ticket and is looking for a Th_e gang appreciates the fine service given by MS, former 1.uodulator. Trallic: W0BLK 37, GOP 28, PHR 17. iSL Manager. 50- and 144-Mc. enthusiasts include LQE, MINNESOTA-SOM, Walter G. Hasak.amp, WOCWB (,XX, MOV,.and F'WH. Nashville's Bandspread is a popular - RJF is really after traffio; by using a BC-696 VFO he publication. HOJ says Q.5-er rejuvenated prewar receiver. regularly reports into MSN, Ql\l W, and Trunk Line '' G," He ruus 5.00 watts on three c.w. bands. EUT and ETN have and other 'I runk Lines when necessary. JNC is putting up combined.forces, usi!'-', the call ETN. EUT will soon have rotary beams for DXCC. The gang at Rochester now totals 813 on 28-, 14-, and 3.85-Mc. 'phone. F'LS got that new 85, an increase of 12 over last· year. The 28-Mc. net of six beam warmed up on 14-J\lc. 'phone and worked WAC in members is going strong each night. ITWG is back on 3.85 ahout three hours. MZK replaced beam lost in storm. Mc. after a Jong absence and will soon have a kw. there. KG6DG is a Chattanoogan on Guam looking for home area GUL has a new· rig-·--400 watts c.w. and 300 on 'phone. on 14-1\lc, c.w. Traffic: W4PL 657, BBT 8~. CZL 28, ETN JDO visited WAO, TPN, and UWG. GPQ is working on a 2,1, DIY 22, HOJ 13. · new VFO. RAJ's shack is getting its face lifted. HFB is a new call at Albert Lea, bringing the ham population there up to 5. ~'IT is increasing power. YUN is QRL with tele GREAT LAKES DIVISION vision studies. IRI\I is working on a 28-l.\lc. converter usiDJ; l7ENTUCKY-SC.M, W. C. Alcock, W4CDA-The a grounded grid r.f. stage. lvl'l'H is back on the air using. a J.\.. Kentuck.v C.W. Net (KYN) operate,i daily 7 P.M. Navy GL9 trausmitter. The moat important of ZWW's fCST) and~ A,M. Sundays, with 15 towns represented. KYP .latest acquisitious is an XYL. Ole Uncle FUZ, one of our ('phone) is trying 10 P,M. daily schedule on 3955 kc. Nets ex-SCMa, plaus to be in Bemidji this summer. Watch the will suspend for the summer June 1. F'BJ is building 24- increase in 144-Mc. work around the twin cities! Thlrty ~lement hearn,_working with BPE on ori;anizing KYE (:K:y. BU-/i22s have Le,m purchased in that area rc>centlv. Do you Emergency) Net on 145.8 Mc. BPE IB trying 2300-Mc. want a frequency check down to the last cycle? YBM has cavities. MDB and KFl are new men on 144 Mc. ALR is Sangamo Type G Mica Ca pacitors are used extensively in Collins Transmitters. The India Supply Mission has purchased :fifteen already served by All-India Radio. They will 1,000 watt broadcast transmitters and all implement the new government's policy of associated station equipment from the Collins taking radio to all people, wherever they live. Radio Company, Cedar Rapids, Iowa. This The government also supplies and operates equipment will be used by the All-India Radio, radio receivers in public places for those who the new Indian (not including Pakistan) govern cannot afford radios in their own homes. Inter ment's broadcast chain. The 15 new Collins ested groups, gathered around publicly _owned equipped stations will be situated in areas not loud speaker1:1, are a common sight in India. Quality Counts Yes sir, quality counts in ham radio as well as in the professional field. Play safe ... insist on Sangamo Capacitors and get high-quality, precision-built capacitors that will keep your rig on the air and give top-notch performance. Get ac quainted with the Sangamo line today. Your jobber can supply you. 81 total WM 1525,-which i8 fine bU11iness. Recent appolntmenta QBS are new additioilll to the 80 C. W • .A.EC Net. UZX and include PNY 118 ORS, LBH ""OBS, and EOO as EC for KTF, NCS of Groups One and Two, respectively, keep Belmont County, We see by the news12ap_er that PGR ob things active wifh two regular drills per week, During the tained medical advice via the HOOT OWL Net from Doc past. month simulated emergency te-Sts were held with the 4INY. which enabled him to give emergency treatment to assistance. of the J;(lmg in the Triple Citiea {Binghamton, hi,, wife until a. doctor could be located in the vicinity. From ,Tohnson City, and Endicott, N. Y.), with traffic being moved the Dayton Amateur Radio Assn. Bulletin, we see that CEO swiftly from 144 Mc. Net in N.Y.C. via 3.5-.Mc, c.w. with hM the unique di,,tinction of having taken (and passed) the :~JQD and FCG as 8.5 Mc. liaison stations. All 3.5-1\Ic. c.w. Clase: B licew,e exam twice in one day, and in different stations are invited to tune to 3600 kc. any night at 8 dtiel!I, too. When he took the exam in Cincinnati the R.I. o'clock. AEC picnic will be held June 27th at Bethpage S.P. somehow lost the paper, 'l'o make up for it the R.I. looked Queens: NZ,J is giving his time to t,he AEC Net on 144 Mc. up CEC in Dayton that evening and j/;:>.ve him the exam KDB is reporting into the 80 C.W. Net. WFY has new a.gain. It was Inspector Oakes of the Detroit office who was VFO. The Sunrise RC is changing operating time from 1030 kind enough to do this for Jim. From the Central Ohio Radin to 0800. W.HB is secretary of the Trylon RC, which meets Ulub News, we see that WZ has" new Collins 75A receiver at, 63-44 Wetherole St., Rego Park, the last Tuesday of each and that NPF has recovered nicely from an appendectomy. month. OG is on 144 Mc. "I'he Staten Island Amateur Radio From the Q-li we note that visitors at the March Springfield Association reports the club net meet.a the 2nd _and 4th .Amateur Radio Club meeting included out-of-towners Mondays on29.6 Mc. at 2100. At present AMO, U.HK, JLC, TDI, HHR, TRT, RHG,and2NIO. From theJIIKE AND KZU, PZP, and VJU are reporting. ACZ and AMO are on KEY, we find that the new officers of the Greater Cincinnati 3.8-, 29~, and 144-Mc. 'plione. CQR is prettyinf, up a 522 Amateur Radio Assn, are: PR, pres.; 4HAV, vice-pres.; for 144 Mc. GHT and WNW are working_ on 522s. NHB. MGR, secy,; NDN, treas. We note also the new streamlined ORB, and PRP concentrate on 28 Mc. PZP and R VL are appearance of the paper, which is now printed professionallv working on 235- and 4.50-Mc. gear. SGO is on 7 Mc. VJU is (Planographed), allowing the use of photographs. The ec:li really high - on 30()() Mc. no less! VYY pounds brass on tor, MGR, is doing_ a fine job on the paper. A recent Class A 14 and 7 Mc. WOZ is on 28-Mc. 'phone. '!'he Pederation of tfoket is that of LBH. DAE made WAC in 5 hours 29 L.L RC hamfest is scheduled for Nov. 12th. MSK i8 giving minutes on Feb. 14, which to us seeD'l8 pretty good since Mrle practice at 1930 on 29,076 ko.. RT has new Temco rig. we have been trying for years to make WAC and have not VVN will operate portable on 28 Mc. this summer ancl a11cceeded, JFC worked l\II3ZJ on 28-1\fo. 'phone during wants schedules. Contact him at 574 W. End Ave., N.Y.C. the DX Contest. THJ says that the Piqua Radio Club now 24. PWJ is on 3914 kc. from 1000 to 1600 daily. UZX. has a 1500-watt emergency gasoline generator available and Q¥Z's assistant, has completed a 30!TH rig. BO will take readv to_go at the first sign of an emergency. W AB reports traffic for direct contact with Alaska and South Pa.cific. t.hat'EYE is conducting code practice on.28 Mc. on Tuesdays HXT finally made 100 countries. EC says TL" AP" will be and Thurndars at 8 P;M, in Columbus. PUN worked ZL2BE discontinued for the au=er. RTZ schedules 6YDO/2. ou 3.85-Mc. phone March 15th. PTF was appointed chair TUK got on 14 .Mc, with converted 459A and finally worked man of l\1ontgomery County Red Cross Communications KDC on 3.8-Mc. 'phone. BGO handled some Central States Committee following the resignation of CBI from this post. tornado t,raffic. VVZ has a rotating double triplex beam. Glad to hear that CNO, Mrs,' Thomas, a re.al old-timer, had GG i8 tmatee of YKQ, Lake Success RC station. Trallic: her ticket renewed and hopes to be back on the air in the W2TYU 840, QYZ 531, 6YDO/2 226, W2RTZ 157, OBU near future. BYE is a new ham in Delaware. WRN reports 143, UZX 128 TUK 126, BO 99, EC 91, :KV4AF/2 8i, t,hat ZHS, an active 144-Mc, man, has moved to .Florida. w·2vos 83, BGO1 60, MJO 58, OUT 57, LGK 36, KDC 35. In closing, I wonder how the Ohio Council of Clubs is pro H.QJ 16, PWJ 14, HXT 10, AYJ 4. gressing, I have not had a single report from them since NORTHERN NEW JERSEY-SCM, John J. Vitale, their o~ganizational meeting_a_ome time ago, Traffic: W8TKS W2IIN-Asst. SOM, 2ANW. NNJ Net (o.w.) 3630 kc. 317, RN 174, UPB 159, FFK 156, CBI 128, EBJ 104, PZA 7 P,M. daily except Sunday, N.J. 75-Meter 'Phone Net 9 86, TAQ 49, WE 49, UZJ 46, PNY 44, ZAU 42, PUN 28, A.lit. Sunday. Tri-County Radio Assn., Plainfield, devoted TNB 24, WXA 24, LJH 21, WAB 18, PIH 17, EIU 11, QIE its last meeting to emergency operation. Speakers were IIN 8, THJ 6, BEW 5, AQ 2, DAE 2, JFC 2, UW 2, NDN 1. and ANW. The club meets every Monday at 8:30 P.M. at City Hall. Officers are BU, pres:; QJR, vice-prea.; MGF, treas.; KHK, secy. Field Day te,arns are testing gear for the HUDSON DIVISION big day. The Monmouth County AEC Emergency Net holds ASTERN NEW YORK-·- SCM, Ernest E. George, drills evecy Monday at 8:00 P,M., under the leadership of E~ W2HZL_-The New York State Traffic&: Emergency County Coilrdinator VQR, with M many stations as 40 Nethaa addetl USH, SXR, JPE, WEK, GSB, and SUL to its regortinl!: in. APL received hi,, A-1 and RCC sheepskins. membership. 'I'he net now consists of 32 members and 41 O<.,C and QMZ soon will be signing /4. UYY is on 144 Mc. out.ride stations actively participating - an excellent per UWN i,, putting up six-element beam on 144 Mc. UZK and formance. BSH reports his new VFO is working fine into his UNA are putting up sixteen-element beams for 144 Mc, YCS :JOO watts with excellent operation into West 't:)oast on !l.5 is on 144 Mc, with 522. O2erators at OEC are QEM and Mc. TDT, secretary pro tern of the Mid-Hudson Amateur SLW. QUH now is 6COD. ~ZF is new member of 75 Meter Radio Club, reports the club is preparing for the radio end 'Phone Net. GWK has 80 countries on 3.5 Mo, OXL is in of r.ommunicattons for the Albany to New York outboard creasing power and changing to VFO. ZI and SUG were motor boat races. EQD is busy organizing emergency net guests at the recent NNJ meeting. NNJ Net will be on systems. Our nets have been drilling with N. Y.C. and Hart summer schedule from June I until Sept. 15. BGH i8 assist ford K!OUPS and have run off a 144-Mc,-3,5-Mc. relay set-up ing LF'R in AEC work upstate. Hal is on 144 Mc. with a N. Y.C. to Binghamton. RH is net control station in West 522. CYE baa new exciter, OSQ has been appointed Acting chester. NVB is operating K2NAD, Naval Reserve station Coordinator for Union County. UWK put up new antenna, in New Rochelle, in the net, SYA donated a fine emergency six-element Sterba Curtain. NIY schedulel!I 7BE daily. power supply to the Amsterdam Radio Club. 'I'he club 18 ANW won the latest F.M. Test clock. UCARA i,, on the air gathering books on the subject of radio to donate to the with its new call, GIZ, dedicated Ma Memorial Station to library to 111pplement their supply, It comes out that TJE the late Carl F. Mueller, who WM vice-president at the time comel!I from a. long line of hams, hi,, father bei11g_ an old he passed on. With the 522 on 144 Mc., the transmitter was spark addict of 1907. Appointments this month: ECs: SUL converted by PIX and PIY, the receiver WM changed over and WIK. OES: 'l'DT. ORS: BSH. Traffic: W2ITX Zc:17, by John Balrd, club member, and the coaxial a.ntenna was BSH 16. installed by EIU, chairman of the technical committee, NEW YORK CITY & LONG ISLAND - SCM, above the roof of the three-story Headquarters Building of Charles Ham, Jr., W2KDC - Suffolk: A small group holds the Elizabethtown Chapter, American Red Cross, where regula.r drills on 144 Me. weekly, UGH i8 going to boost his the station is located and where meetings are held ever;, a.5-Mc. c.w. output with a pair of 809s. PIA lias a 144-Mc. Monday night. Mrs. Mueller bas dedicated the use of Ca.rl a beam rotating with hi,, 28-Mc. antenna. ZV rarely misses a complete station to the Memorial and the club is going to day on either 3.8-Mc, 'phone or 3.5-Mc. c.w. MZB has put it on all of the lower frequency bands. MUP WM chair joined the 144-Mc. gang with a 522. EBT is getting another man of the Dedication and Memorial Dinner which was fi22 in shape for the_ car. WLS is on 420 Mc. with r.f, units held at the Eliz:1.beth YMCA Apr. 17th. HIN, from Head from an AI'S-13. WXJ joins the gang. ADW is on 28 l\,1c. quarters, represented ARRL. PIX, the resident, presented with !lO watts to an 8298. From his new QTH in Oakdale EDF is on 28 Mo. OQI gets on 144 and :3.5 Mc. Nassau: ~!:!cn~~tV;e~ ~Hii ath~<~l J~.~n~~!XutJ~m~~b~a~!Y& With an average of 27 stations active on r<',gular drills on 144; ~andmade scroll. UN presented the Past Officers' Keys to Mc. the Nassau gang heads th_e section. Those active dnring J\IUP, NKD, LIQ, PIX, and Mrs. Mueller for GIZ. New Mar<'ll were: Cl\1U, FQW. IER, UOL, MBR, VT,, iiWV, .ECs arc CHJ, Avenel; BTZ, Rahway; AUI, WoodbridgP; CET, GG, QBS, OBH, UQP, SP!, TVX, RZ, CHK. IGP. f>l'V, l<'or,Jii; lZC, Cranford; 5UD/2, Elatontown; DME. ANN, SMX, JPV, CB, WKR, LPJ, HOL, Fl, NI. \VJS, At.Iantic Highlands; NIE, Interlake!!.; OOC,.Sea Girt; NUL, RH, QAN, VQY. ADT. OXM, OUQ. and NBQ. Regular Passa,i(' County; Z.L, Avon. B'fZ is urs. OSQ is organizing drills include (JSP traffic from NaAAau t.o the Monmouth t,he Unio,n, County Emergency N~t on 1~4 Mc. with tie-in on County, N. J .. AEC Net. Brooklyn: NXT got going with :..8 Mr,, lhe UCARA-RC Net 1s runruug on 144.138 Mc. a.m. on 144 Mc.; KU doubled the'number of dements in his Sun. 11 A.M. with GlZ as NCS and PIY in charg~. 'I'raffic: beam to eight with the assistance of HG. JSJ ia back on 14.4 W2GGG :H.5, OElC 138, DRY 112, CQB 111, NKD !Oil, Mc. with a sixteen-element beam. WLI, UQA, and J!JYD ANW 96, LFR 86, NTY 74, MTV 5~. BLS 49, BZJ 26, QEM are recent arlditions to the 14.4-Mc. AEC Net. ElPF is active 23. APL 20, OJX 16, BRO 10, KMK 10. UWK 10, OXL 9, on 144 Mc. OHE is equipped with both vertical and hori IIN 8, QMZ 8, ANG 6, CWK 5, '!'RN 5. zontal beams for 144 Mc. 80 C. W. Net: PVR, UCB, and (Continued on page 84) 82 'll:'5r~~ FOR CLAR IT Y AND RUGG E D NESS I N PORT A 8 LE WORK I JUgh Artieulation · H" New1. Economicall 1gh articulat·10n g t .th message th rough e s e listener f t' ... lessens 1 Sr,de-to-talk a 1gue. H',gh output " relay control swit h . 48 cable . H ang-up hookc . Model 215-SR. . Carbon. . List Price $ Model 615-S . . . . IO . R. Dynamic. List Price 2 Send for Bull · .... $ 0 etin No.137 "'•'.':'<•,N•.. •• NO .FIN.. E.R. E'leemY~ ELU:UO•VOICE, INC., BUCHANAN, MICH, Expdrt: 13 E. 40t~.~t., New York 16, U.S. A. Cables, A~lab AUTHORIZED DISTRIIWTORS EVERYWHERE Send for Catalog and fact-filled "Century" Crystal on Carbon -Model 210,S "Cardax" Cardioid Crystal Dynamic-Model 610 Bulletins loday Desk Stand Dynamic-Model 600-D with Dual Freq. Response, Crystal - Model 910 Crystal Microphones licensed under Brush Patents 83 MIDWEST DIVISION l')ay contest iOO per cent wlth lour tra.nsmltters in opet!l• tion. HVX is new ham in Keamer,. 1''JU and MLB are on 0\VA--SCM, William G. Davis, W0PP-IFI is re 144 Ille. MLB has new HRO 7.' Twenty-nine hams at 1 cupera.tinl!: from a heart attack. JUI is now up and tended the reorganization -of the Western Nebraska Ama around aftr.r a siege of t,hP s'.tm(' t,ro11ble. T.TC has new 400~ teur Radio Club at Gerinp:. RGK, LWS, and RYV are wattr>r going. fIRj\1 is new ha..rn at Linn Grove. SEF _operates president, vice-president, and secretary, respectively, lVIGV on 14 Mc. pa.rt time. B:;x-FSH now is GZ. W MP made WAC ~ave a fine talk on s.s.s.c. and held a discUBSion on oscillo with his new p.p. 818 final. A YO is buildin!!i new exciter. PP graphs. A fine time was had by all as can be vouched for wa.a reelected to town council. EBK~ of Qlear Lake, is on by CVC, UBN, and your SCIII; who represented the North a.85-lllc. 'phone. LAC has outstanding B:;C aet-up in Bur Platt.e gang. The group will participate in Field Day. DJB lington. HKN had a firn in his rip:. NMA is keeping contact ison with a BC-610andSX-28. LJOhasapairof 811a i,erking with Iowa. Net with one of two rigs set up in his CAA truck. on 3.5-28-Mc. c.w. and 'phone. RGKis usinga304 with a full SW! is new EC for Cedar Rapids. DEA, Midwest Division gallon. NYE and VMP will be on Field Day with BC'~654. Director; PP, Iowa SOM; and YP, Iowa SEC, attended Traffic: W0FAM 198, sAI 48, FQB 4,5, HSO 15, YCG 15, Cedar Rapids Radio. Club meeting May 12th. WMU re FBK 8, NYE 4; DHO 2, WYE 2. ports workinl!: HB9CS for solid ten minutes on TLCN net frequency a,560 kc. using BC-349. He has a new Federal ltl7-BY which he expects to have on the air soon. Trunk NEW ENGLAND DIVISION Line '"K, 11 under the manage1nent of HJ\.1J\.1, be~an opera~ f'ONNECTICUT- SCM, Walter L. Glover, Wl VB -·- t,ion March 9th. Trunk Line "K" consists of EVJ, HMM, _.. 'l'wo new cl11bs were organized recently: The Matta tuck ARR, and 5LSN. AAL sees poSBibilities for portable 28-Mc. Amateur Radio Societ:y of Waterbury, and the Meriden rig on tractor. OSC, Storm Lake, is on TLON. TTL is on Amateur Radio G'lub. Officers of MARS are OMW, pres.; 144 Mc. v.itb lOOTHs. AER, TIO, CHI, NFM, >1nd wee !ZG, secy. and treas. Officers of MARC are FYG, pres.; were heard by TTL on 144 Mc, OTD, Nevada., is going to HVF, vice-pres.; QPD, secy.; NRG, treas. JE of Worcester, high power on 144 Ille. with 829B. AEH hears WflZ, who Mass., is looking for a Connecticut station for the Swing uses a vertical on 144 Mc. SQQ is EC for Adel and vicinity. Shift Net at 12:30 P.M. BAX, DJC, and LMK visited CQ NAY has applied for EC for Bloomfield area. CVU broke out Radio Club meeting. CQ has received the call RBS. ITM 654 and set 3970 kc. upside down in the Middlewest, Traffic: has a new Jr. operator. Bob Perry, of Stratford, passed exam W~HMM 1056, F'P 44, CNK 36, PP 2,8, AYO 25, QVA 24, with call RBP. ON and LVQ made Class I 00 in January SEF 21, OSO 20, TJC 17, F'KB 15, N1v1A 2. FMT. BH:M. reports over one hundred countries worked. KANSAS - SCl\I,. Alvin B. Unruh, WM.WP - Al.I AW has new opera.tor Dick Eide!, 2MRW. 9BRD/1 has 30 Kansas Emergency Coordinators have been given added countries with indoor antenna. NJM attended Old Timers responsibility by decreasing zones from 33 to 22 and stream Night in Trenton, Mar. 27. Joe Dietz is waiting for call lining the set-ui,. Ees plus RMs, PAM, etc., meet the first after taking the exam. KUN and KUO went down for their Saturda~ of each month. Assistant Ees are invited to take Class A tickets. IGT received appointment as EC for New pa.rt. OZK is EC for new Zone 10 - Cowley.,_ Sumner, and Haven, AD'\V has new VFO working. HCARA conducted a Harper Counties. ZOC and AHA joined AJ;;1_;, ZOC is new Red Cross drill on Mar. 21st wlth 25 members and 7 mobile ORS and has pair of 807s driven by BC-457 and, BC-4.58. rigs participating, and got a nice write-up in the local paper. OHX says 3.5-Mc. rig is ready to go, and reports VZL has DWP is finisbi_n_g his rotary now that goool WX is here. kw. IZJ has ARC-5144-Mc. rip:. CUL reports eight members l.KF has CRN Net in operation. All clubs seem to be making in N.W. Kansas. (EC Zone 21.) CXF' has schedules with bip: plans for Field Day .June 12th and 13th. As per the VP4TU and W5EUF/KH6. AHA is on slow speed t,runk change in .i;u.Ics, please a.ddre~ your 1ness3._ges to your SEC,• line and handled more traffic. He also has schedules with W,5 VW, 41 Middlefield Drive, West Hartford. NARL held an and W9, ARM is looking for schedules with chess players. AEO drill with New York City F'eb. 8. DXT rebuilt BC-654 Engineers of the telephone company gave a lecture and for VF'O. NJM converted an ARC-5 for the s"me purposa. demonstration of their mobile two-way telephone at a joint HUM received ORS appointment, and reports into Nutmeg ip.eeting of the Wichita Amateur Radio Club and AIEE Net. VW, as 00, reports logging 42 c.w. and 39 'phone sta~ chapter. Weli over 100 were present. DWC, OKD, MAR, tions out of band during DX Contest. We also notice con and A WP have BC-453 Q5-ers and report ham bands have siderable reports from Obs on 2nd harmonies of 3,5-Mc. band. widened considerably. OZF' and ZUA were Wichita visitors. Better check, fellows, before the FCC does. Traffic: WlAW KSY reported into QKS Net from FER, Hays, who has VF'O 279, DAV 253, 1%'\V 220, LKF' 161, VB 138, NJM 131, going. MKR is active at El Dorado with 800 watts. Traffic: INF 119, KUO 11, ORP 61, BDI 42, .FTX 33, ADW 13, W0PZP 114, NJS 36, AWP 35, !FR 22, OXF' 20, WKA 20, GT! 12, DXT !.I, DWP 3, BGJ 2. AHA 16, OUU 14, CUL 8, FER 8, ZOO 7, F'RK 6, AHM 5, MAINE-SOM, F. Norman Davis, WIGKJ-SEC: JTN4, AEY2. LNI. RM: NXX. PAM: FBJ. New OPS; VV. New ORS: MISSOURI---· SCM, Mrs. Letha A. Dangerfield, KYO. RBD is new amateur in Wilton, NXX has an SCR- W~OUD -ARR started building a table rack with a pair 522; he also sends code practice daily at 7 :30 P. M. between of 1625As and VRX680 exciter and burned out his antenna 3500 and 3550 kc., the exact frequency determined by inter relay. The Columbia boys piled up a lot_of traffic with the ference in this re,pon ! LKP and ODA are doing fine job as St. Pat,ick's Day celebration at the J,Jng. School. The boys links between S.G.N. and P.T.N. for clearini traffic. NKM are takmo: turns reporting on MON. The regulars are CKS, ha,i acquired an SCR-522 and a BC-696. QI!,J now operates OEP, J'SR, and ZZW and the c,lnb station, ZLN. JSR ia from KlNAD. JAS is at Duck Pond for the summer. The puttinp: up new 3.5-Mc. antenna. JHH has a Stancor 60N. column "With the Radio Amateur," written by YV. io PXW has an 813 on 3.85 Mc. and a BC-459 on 7 Mc. AF'U without doubt the best publicity New England amateurs is a new ham on 7 and 3.5 Mc. NNH heard the Hallicrafters receive. Don't fail to read it in the Portland Sunday Teleoram. F!xpedition twice while it was in tbe mountains. RAB and l{YO bas new NC-173 and his XYL is learning the code. HDK have a new Stancor 202A with 125 watts on 3.85, 14, AWQ is on 3.85-Mc. 'phone. QUA has worked half the states anrl 28 Mc. and RAB worked 28 other YLs since January. on 3.5-Mc. c.w. and he is running only four watts. If all the F'S! likes trailic work. He s~ys the St. Joseph Club has been boys that are bearing down at the code and theory classes reactivated. The Springfield club has been afliliaterl with held at the PAW A pass their exams we should be hearing ARRL. Vl\iO burned out a bias supply. Director DEA bas quite a few new calls in Portland and vicinity soon. Field received rPplies from 25 per cent of those he polled. Correc Day is coming up; get your batteriea charged and let 110 tion on that Mo. 'Phone Net- it, is 3903 kc. KSR is NUS. hope the weather is better than last year! How about more VMI's p;an11: did fine work in the Bonne Terre disaster re reports on tbe first of the month? Traffic: WlNXX 60, ORY cently ..F'ive of the hoys went tQ the scene and used the call 60, LKP 44, GKJ 41, POD 36, ORT 31, QHA 28, JAS 24, KSR/0 while many others relayed traffic froin their home Iii§'. AWN 17, vv 15, AFT 9, KEZ 8, PTL 8, KYO 3, statioDB. There were nice write-ups in thP- papers. 11"he only ealls l know are OMG and QMF. OUD has better signal EASTERN MASSACHUSETTS - :SOM, F'rank L. reports since DE added more wire to the antenna and ran it Baker, jr., WlALP · · New EC for Beverly is BVL. WU and around a couple of more corners. ZAO proposes shifting the Q.TB are new ORS. BGWisa new 00, Class I. NF, GOV, and Mo. c.w. emergency frequency to 3650/7180 kc. to make it AYO renewed 00 appointments, HOB his OPS, and JXH more usable both nip:ht and day. INK had a personal emer his B:;C. Ml\IH has applied for OES appointment. CTR is on gency when he ran into a clothesline in his eap:erness to 144 Mc. ALP is on 144 Mc. with a 522. AKY's brother in re_portan SOS to the Patrol. Traffic: W0ARH 306, QXO 216, Sweden is Sl\I5APF'. AWA, RHW and PWP a.re on 3.9 Mc. SKA 138, GEP 58, ZZW 57, OUD 56, KIK 49, JSR 39, Sorry to have to report the death of OTO. PEK, from ARRL, VMO 33, CMH 31, CKS 30, FSI 27, KSR 23, DEA 21, and ALP attended meeting of South Eastern Mass. ARA NNH 21, VMI 11, URR 8, ZAO 8, TAB 6, HDK 3, PXW 2. in. New Bedford. 8WGF'/1, PHA, VX, NDI, NAD, and . NEBRASKA-SnM, Wtlliam T. Gemmer, W0RQK - 0 R'r are on 144 Mc. IIIEV has a. sharp Superhet on 144 Mc. DJB, FAM, LJO, YCG, and WII/0 are new ORS appoint QQL, QPB, QZO, QJS, and JOY are on 144 Mc. Plymouth ments. MZl\I is looking for the "ole 160 gang" from a. new Amateur Radio Club now is aflilia.ted with ARRL. The QTR, Wakefield. BQP is now 9DF'M and operates around Sub Signal ~a.dio Club had dinner, movies, and a radio 7241 kc. ZTE's 3.85-Mc. vertical and SAI's mast blew down quiz by KAE. KNI reports numerous QSOs with BZN on dnrinp: the March winds. SA! has a 60-footer lined up for 420 Mc. KN!, NF', and BZN have 2300-Mc. ca,ity osoil replacement. TYO is on 28 Mc. with 200 watts to all 813. lators. MOR has the following reporting in on EC d.rills: DHO is using a Globe King while rebuilding his T-55 rig. AKD, KSA, MUD, NWB, OKK, OTZ, PXH, QHC, and LEF' raised a as.footer. HSO had to trade in GTW for QJK on 144 Mc. BUG is building kw. final for 28 Mc. QMD present call. Fifteen Hasting Radio Club members, their has new dipole on 28 Mc. LMU reports the following are on wives, and several Grand Island hams, visited the monitor the Newton Emergency Net: BL, EK, EYI, RLX, OIW, ing station. SEC MLB says," The MARC will be in the Field (Continued on paq• 811) 84 OHMDTIE DUMMY ANTENNA RESISTORS Rugged new Ohmite units consist of special non inductivelv-wound, vitreou.s-enameled resistors connected" in parallel and mounted inside a sturdy, perforated steel cage. • IMPROVED FREQUENCY CHARACTERISTICS • RUGGED VITREOUS ENAMELED CONSTRUCTION Write for Bulletin 136 wo new dummy antenna resistors, designed by natural resonant frequency as high as possible. For Ohmite for loading radio transmitters or other all practical purposes, these resistors may he con Tradio frequency sources, now offer improved sidered "non-reactive" within their recommended frequency characteristics. This results from' more operating frequency ranges. effective proportionment of the d-c resistance, resi dual inductance, and distributed capacitance. In Type D-101, 100-watt unit, is sto!'ked in 52, 73, ,the new units, residual inductance and distributed 300, •tOO, 500, and 600-ohm values; Type D-251, 250-watt unit, in 52, 73, 300, and 600-ohms. Toi. capacitance are kept to a minimum, making the ±5%. For full information, write for Bulletin 136. See You at ¼he National A.R.R.L. Convention OHMITE MANUFACTURING CO. Sooth No. 103 Sept. 4-5-6 4865 Flournoy ·Street Milwaukee Auditorium Milwaukee, Wis. Chicago 44, Ill. Z'e 7!:«JMwtt40HMDTE R H E O 5 T A T 5 • R, E 5 I 5 T O R 5 • T A P 5 W I T C H E S as OMU, PX, and Rl\1. Newton ARA is going to renew call has been running successfully for about three months, but at NPA. BR put 6AK5s in his 522 receiver. LMU has 522 least one Rhode Island station is needed to handle traffic receiver finished. GGV has n.f.m. job ready for 27-30 Mc. which the net receives destined for R. I. Might 1 suggest to l A COIL FOR MATCHING YOUR TUBE A LINK FOR MATCHING YOUR LINE With the introduction 0£ this new and comprehensive line of in ductors and swinging link as• semhlies, E. F. Johnson brings to the amateur the same efficiency that is achieved in commercial and broadcast components. In £act, the "know how" to design and produce these units is the result of Johnson's experience in building thousands of inductors, matching networks and phasing units for broadcast and commercial services. Efficiency, never before available in commercially produced amateur coils, is achieved by two models for each hand: for use either with high voltage low current or low voltage high current tubes. Instruc tions will he provided to select the plug-in swinging link that will best match a particular inductor to any feed line from 50 to 600 ohms. Johnson air-wound inductors are sturdily supported on polystyrene-not on conventional plastic strips or winding forms. Available in 150, 500 and 1,000 watt ratings, they can he subjected to severe overloads because of heavier windings and better insulation. These coils are spaced to fit conventional, present day jack and plug assemblies in their respective ratings. Also available in all power sizes, is a complete line of semi-fixed link inductors. The coils, jack bar assembly, swinging link arm, "plug-in" coupling link and necessary hardware are packaged individually-enabling the amateur to get only what he needs without purchasing extras. For full information of sizes, types, etc., see them at your dealer or write for new Johnson Inductor Principle of "plug-in" swinging Catalog. You'll be glad you did! link illustrated above. The swinging linkarm is polystyrene. Bracket is nickel-plated steel. Link assembly easily connected E. F. JOHNSON CO. for front panel control. a~ ,eame, lie ''il An Interesting New Application for the 1\-lallory lal-1.. Hamswiteh* This switch may be used conveniently for DC. The multiplying circuits must remain active switching a single meter into or out of 5 isolated in each respective circuit at all times. circuits. Ample space is provided between its Switch No. 151-L comes complete with pointer two switch sections for soldering meter multiply knob, hex nut and lock washer. Dial Plate No. 487 ing resistors directly to its soldering lugs. Thus, has been designed especially for use with it. range expansion of the meter may be had ~uto You can rely on Mallory Precision manufac matically as the switch is actuated from circuit turing to supply you with the most dependable to circuit. line of: ham band switches, push button switches, Use this switch with voltages up to and in controls-rheostats--potentiometers-pads, tubu cluding 1500 volts DC. Because its simple :con lar capacitors, transmitting capacitors, dry electro struction omits the two circuit-closing center lytics, dry disc rectifiers, vibrators, and vibrator sections, it must be used with multiplying re power supplies-practically every component sistors exclusively when measuring the flow of you need to keep your rig in A-1 condition. Send for romplete details on this switch. P. R, MALLORY & CO., Inc., INDIANAPOLIS 6, INDIANA A copy of the above schematic will be sent upon your request. *Reg. U. S. Pat. Olf. 89 on Apr. 8th the Northern California DX Club presented two 18" engraved gold trophies to the club winners in the recent .ARRL DX Contest. One for o.w. went to RM and one for 'phone to TT. The 140,415 points made on c.w. by RM was the highest score ever to be turned in, in this neck of the woods • .l Complete data on the Eimac 4Xl 50A for STL and other UHF Follow the haders to applications is available by writing direct. EITEL-McCULLOUGH, INC. ~.. - 197 San Mateo Avenue, San Bruno, California ~ fU The l'ower for C•F EXPORT AGENT$: Fmar l Hansen-301 Cl•y St.-San Fr1ncls WEBSTER-CHICAGO ?//ou7&' WIRE RECORDER NEW SIMPLIFIED WIRE RECORDER MAKES IT EASY TO CONVERT ANY RADIO SEE YOUR. INTO A WIRE RECORDER COMBINATION NEAREST HAM SUPPLY HOUSE The Model 78 Wire Recorder is especially adaptable for home use in connection with a radio receiver or with a high fidelity public address· type amplifier and speaker. Compact in design with simple push button controls, the Model 78 adequately meets the needs of both the professional and amateur recording enthusiast. Model 78 comes complete with necessary cords, plugs, microphone, 15-min. spool of wire, and full instructions for easy connection. Head phones may also be used for quiet, private play back of a recording, WEBSTER•CHICAGO MAKERS OF WEBSTER-CHICAGO RECORD PLAYERS AND NYLON PHONOGRAPH NEEDLES 5610 BLOOMINGDALE AVE. • CHICAGO 39, ILLINOIS 93 ning Field Day activity again thia year, The Denver Radio Club ia making plans for a big Field Day and haa hopes of running up a heavy score. The committee in cha'lle ia work ing hard to make it a aucceaa. ORB WWI back in Canon City for a day recently. Clay hopes to be,on 3.85 Mc. at Olathe, D!il Kansas, soon. He ill workin~ on maintenance of GCA equip ment for the Navy. WYX 18 busy iDBtalling equipment for the Courtesy Patrol in towns over the State and haa not much time for ham radio. ZSQ haa a new three-element beam for 28 Mc. JBI has a beam-building project cooking. Three YEARLY BINDERS Uolorado amateurs attended a communications conference in Oklahoma City put on by the Civil Air Patrol. Everything was fine until a tornado disabled their airplane, but another ship was sent for them and they were only a few hours late getting home. Trame: W0QHI 23, 1\IOM 16, LZY 13. UTAH-WYOJ\IING-SCM.Ah;n l\L Phillips, W7NPU · -·- The FARi\l Net is doing a swell job of cove,:ing the intcr rnountain arPa - Utah, \Vyominp:, Idaho? Nevarla, 1\1on tana, New l.\If'xico, and Colorado. Net, time is 7:30 P.M. 1\1S1' l\londay through Friday. The net also handles per sonal contacts to all parts of the world. UTM has completed a 50-wa.tt e.e.o./excitcr which doubles as an ency rig nsing a PE-103A power unit. KIY is rag-chc d work- ing traffic on 3.5 Mc. with the Colorado and "ng nets. TST has moved in his new home and is anxious to get back ,,n !,he air. DLR has revamped his final to a balanced tank >tud is driving the 813 with a 274N. OKF isLanging away on a.5-Mc. c.w. with a pair of 812s. JHH is enioving his new home and ham radio. Traffic: W7UTM !J8, RPX 59, DLR 19. KIY 19, Tl::lT 7. SOUTHEASTERN DIVISION A bABAMA - SCM. Dr. Arthur W. Woods, W 4GJW - ft 8EC: KCQ. PAM: BA. Thanks for the FB reports re ceived from many parts of the section this month. DXB works portable from \VUHH, and rccent1y became a mem ber of the Naval Reserve Net. CIU is Class A. BWG is on 3.85-l\lc. 'phone. GOF sold out after marriage, and is t~.autiously reinstating amateur radio now. LRU works on 7 Mc. ADJ and HAN work 28 and 7 Mc. respectively. \\ here is t.he Gorgas bunch"/ MXU works 7 and 14 Mc. from new QTH, concentratlng mainly on traffic. He solicits in quirits for an Alabama 7-Mc. net for daytime. DTV has heeu iustrumental in settin~ up traflic nets a.t 1\lobile on 28, 7, and :3.85 Mc. INU is NCS of 144-Mc. net on 144.7 Mc. at ZOOO CST Wednesdays.. The :!8-Mc. net meets Sunda;i;-• at 2100 on 29.2 Mc. The 7-Mc. net meets Thursdays at 1!130 ,:,n 7025 kc. with DTV aa NCS. The 3.85-Mc. net meet• Sundays at (WOO on 3955 with IBZ as NCS. The XYLs of various mobile hams meet Friday nillihts at 2000 on 29.2 l\Ic. with the YF of DTV acting as NCS. The last session ex ceeded 2H hours. Are there any hall18 in north or south Alabama who would care to rer,ort station activitie•? FJASTERN FLORIDA-SCM, John W. Hollister, Are We Right? W4FWZ -··• Emergency Corps: ALP. Tampa, has program worked out with Red Croa,i and other agencies plus wcll pl"nned AEC set-up. IQV, Lake City, has program with Red Croa.~, FPL Co., Federal, and State J!'ore.stry, State Police Radio. The 8tate manual is based fundamentally on You should have at least Chap. 22, 25th edition ARRL Handboo~. Check your emer <;("ncy gear. ls everything which might bec required on hand? two of them-one for your Cortez: DQW requests that every station located where there !fl no RC write him and volunteer for the assigr:i:ment. ,fax: DU is now knocking 'em o.lf with .BC-610. NKC, on complete 1947 file of 28 Mc., ill laying out lines for rotary. A WE reports no B.C.I. "ith n.f.m. on 28 Mc. Lake City: HLC is on.28-Mc. n.f.m. copies, and one for each with 8005s. Now that CPG baa moved there IQV can set '!P 144-Mc. circuit. St. John Club. members are NN. AGB, HLC, and IQV, with CPG looking in. Miami: BT schedules 1948 issue as published. OBS now at 11 P.M. ES reports· USCGA 7CGD includes Puerto Rico, Caribbean and Canal Zone. BYF sent an un told number of 00 cards during the DX Contest. BT made WAC! JA Vis KP4 now. NLS is on 28 Mc. with 813. Down • flame the beall18 of !KI and VY during sq_uall. KXO and JAV made RCC. Sixtee,'!::,vear-old NCP ill on 28 Mc. with With each Binder is furnished a sheet of nice beam. IYT, new On.c, haa 813s on 28, 14, and 7 Mc., and reports 99 countries with vertical 7 Mc. and full-wave gold and black gummed labels for 14 Mo. West Palm Beach: FNR reports 50-Mc~gang lined up for state QSOs. 144.-Mc. net membera: DU"[1.-FLH, years 1929 through 1949. The proper FVW, HBF, IPW, JIP, KKU, KMM, LIP, LUS, M!'IL, VV, BRB, DCF, F'NR, !SR, IUJ, AL~, AYP, DOM, DES, one can be cut from the sheet and t~?k~il: &i~·Li~?oJWi'ro EKCJ~\1il1i1trMlJ: GIJ, GfY, GJO,.t MJP, QN, IQV, CPGi_D.OW, IMF~NEE, pasted in the space provided for it on MK.I, AY:l£,. 01,;C, GFE, GMl,.!-.fGA, natlio: W4I V 257, AYV 194, .1!.S 110, AAR 97, LIS.I 51, DQW 44, M T 29, the back of the binder. BYF 28, MKP 26, BT 25, FWZ 25, MNT 25, DEP 22, ERU 19, KMV 12, LJM 10, MVJ 9, PEI 7 AFF 5. CANAL ZONE (Special report)- KZ5AW reports FS monitoring 3.5 Mc. to find a spot for 3.5-Mc, net to tie into F1orida Palmetto Net. 'rhere waa a lot of activity in the DX Price $2 .00 each postpaid Contest and one score over 100,000. There ara 75 stations in Canal Zone now. FS is RM for Pacific side and AX for Available onfy in United States and Po.sseuion, Atlantic. LoJJally, the trafl\c net will pass information around the Istbmt18. Trame outlets throucl, Florida and other spots THE AMERICAN RADIO RELAY LEAGUE are needed. The CZARA, under Gb aa prexy, threw a ham fest that will set the pace in the future. Beat QSL WIUI shown West Hartford, Conn. (Continued on page 96) 94 PLASTICON Plastic Film Oil-Filled CAPACITORS I. More Economical 2. Smaller-Lighter :1. BettPr Electrical t"Jharacteristics 1. More Economical MFD. Volto List Price l"'ist Price Saving DC Paper Capacitor Plasticon AOC 10 1000 $15.18 $10.67 $4.51 4 2000 13.67 9.24 4.43 2 3000 22.73 15.40 7.38 1 4000 33.54 27.50 6.04 2 5000 •18.73 41.25 7.48 AbO:ve are. typical examples. PLASTICONS are the result of teehnolouleal advances ••• cost less to D1.annfaetnre. attve better performance 2. Smaller-Lighter 3. Better Electrical Characteristics Approx. Paper Approx. Weight Cubic Dimen5ioris Capacitors Plasticon6 Volts MFD. DC Power }~actor at Paper 85°C 60 cycles 0.7% Paper Plasticons Plasticons 0.3% Capacitors Capacitors Resistance at 85°C megohms -- per Mfd. ,1() 100 lhs. 31 cu. in. 30cu.in. 10 1000 l.95 1.71b1. Capacitance Ten1p. Goefficien t l 00 4 2000 2.0 1.23 31 23 % -40°C=73% -40°C= 94% at 25° +85°C=97% +85°C=I03% 2 3000 !tO l.21 31 19 l'LASTICON CAPACITORS given are Type ' AOC. mineral oil-filled. I 4000 1.77 .94 28 19 PLASTICON ASC oilicone-filled have hetter characte.ristics. 2 5000 5.2 2.9 70 60 Paper C.:apacitors given are chlorinated diphenyl impregnated. @ . · P. (~ondenser t•roducts (";ompan11 1375 NOltTH BRANCH STREET • CHICAGO 22, ILLINOIS MANUFACTURERS of GLASSMIKE CAPACITORS and HIGH VOLTAGE POWER SUPPLIES 95 .-..-..-.-.,-,-..-.-..-.-..-.-.-.-.-.. by JB. The big prize. a VHF-152, waa won by LN. MX io ex-W4IP (former !:\CM of E. Fla.). Ham examo are given ( ) on the second Friday of ea.ch month at Corozal. WESTERN FLORIDA - SCM, Luther M. Holt, ( '.l.~e .L-1.lt.R.L. ) W4DAO-ADW ia a new-comer to our section; he teaches school at DeFuniak Springn. Welcome, OM! ECT/FJR have ( ) an ll'B electronic keyer. NJB bought a new receiver. NML is newest nail at Pensacola. ACB, our SEC, wants informa tion as to who in the section is Cl.ass A. If you are Class A t please drop him a line. I.T promises a visit to Pensacola ANTENNA BOOK : gang soon. KYJ worked Pensacola on short akip. QU built 28-Mc. rig. QK bought surplus VFO. JPA oj'.leratcs mobile (' llas Wl,ate,,er J"ou Want! ) exclusively. ltIZ wants 3.5-Mc. antenna. MZJ has ART-13. MEN is planning more Q<:>Wer. LCY plans activity soon. JV rune· kw. on all bando. EQR erected towers for long wire. 1 CHAPTERS : Wewonderif itspella 7-Mo. work for him. DXQ made WAC on 7 Mo. MUX plane on changing_ QTII. FDL moved to Evergreen. MOB ia rebuilding. NFN works DX. NFM had f Wave Propagation ) trouble with final amplifier. DZX went n.f.m. Traffic: Antenna Fundamentals II W4AXP47. ( Ground Effects .J GEORGIA--SCM, Clay Griffin, W4DXI-Don't Feeder Systems II forget to mail your activity reports so I will receive them no ( Half-Wave Antennas J later than the fifth of each month. LNG sent a fine report on I Long Single Wires ) v.h.f. activity. He reports LNF and KHL hold Georgia 144- • Multiband AntennaR Mc. record with 100-mile contact. LNG operateo on 14, 28, 50, 144, and 236 Mc. with p.p. 24Gs. He baa sixteen-element ( Driven Arrays ) beam on 236 Me. BOL acquired a BC-639 receiver for 144- Parasitic Arrays II Mc. work. LJB has a BC-325 transmitter in operation. JDR ( ''V" J\ntennas J plane to put up a three-element 14-Mc. beam. BOL and DXI ( Rhombic Antennas ) chased DX on 3.85 and 3.5 Mc. during the winter and spring, with fair success. BOL's beat was ZL on 3.85 Mc. DXI needs . U.ll.F. Antennas ..• Asia for WAC on 3.5 Mc. 'l'he Fulton DeKalb Net has about ( Special Antenna Systems J 35 members with LNG as NCS. BIW has__portable-mobile . Finding Directions _• equipment for operation from 3.5 to 28 Mc. The Cracker Net ( Supports and Constn1ction J still needs a rehable outlet in Savannah. ·we would like to Rotating Mechanisms II hear from stations interested in ARRL appointments. ( Receiving Antennas J Traffic: (Feb.) W4BVK 374, KV 118. (Mar.) W4BVK 87, DXI9. WEST INDIES - SCM, Everett Mayer, .KP4KD - ( Ht, page~, in ••QST" format. : The KP4 gang was saddened by the sudden passing of KP4DY, ex-K4FAB, on Mar. 16th. AM worked all 10 U.S. : 5() cents, postp_aid. No stamps, please! ' ) districts on 27- and 28-Mc. 'phone on Mar. 25th. He worked PA0 for a new country and schedules KP4CE/W8. BE WEST HARTFORD ) worked G3 and has nice rag-chews with W!!FFB and f W3KBE, The Radio 1<1otilla of the U.S.C.G. Auxiliary ' A.R.R.L. CONNECTICUT ) sponsored a broadcast Mar. 18th on which the SCM repre sented ARRL. AQ was the spark plug. The PRARC spon sored a hroa.d.cast on WKAQ, Jenny Ramirez, ex-K4ll'OW and XYL of KP4DY, gave a 15-minute talk on the dub aims and activities. _'!'he PRARC is running code classes for ··------· beginners at Central High School on Tuesdays and Thurs days. FD returned to P.R. from Atlanta. FP bought HT-9 r.______. from AU, who plane a kw. on 28-Mc. 'phone. CN moved to new QTH. :FU and OT made debut on 28-Mc. 'phone. ES I was granted an OBS appointment. Watch the Ground Wav, for schedules. SOUTHWESTERN DIVISION TOS ANGELES-SOM, Vmcent J. H!'ggerty, W6IOX .l..J -Asst. SCMa, W. J. Schuch, 6CM~, and Irvin O. '/;Ip to the m;,n1,1,te Hege, 6FYW. Los Angeles YLRC news: G2 x O was guest at March meeting held at home of QOG. Fourteen YL/XYL operators were present. CBA _and C,'EE are new YL and XYL operators. respectively. UXF worked Tanganyika on 28-Mc. c.w. YRL has 60-ft. steel tower for 28 Mc. NAZ ia on 3.85-Mc. 'phone and 7, 14, and 28 Mc. UHA has con THE firmation on LAS and VP2 DX; she runs weekly schedule with KAlCB. QOJ has 101 countries on 14- and 28-Mc. 'phone. TSL ran 'phone schedule with KG6CN. WSV's DX is Alameda; she also sent in this report. AOM, BXZ, ZCE, LICENSE MANUAL PAP, and WUY form the "Pacoima Hair Net" which meets Wednesdays at 8 P.M. on 29.4 Mc. Pasadena Short Wave Chili news: Club meets second and fourth Fridays at is always kept up to the minute. We insert 736 Rosemead Blvd. Technical talks, "Board of Experts" correction sheets whenever there is a quiz program, used p!)orts auction, and movies are some of the club's activities. AEE is on Mission Trail Net; he is fixing change in the amateur regulations which s.s.s.c. exciter for 3.85 and 28 Mc. PFO is building kw. rig cannot be incorporated in the printing with 59¢ 304TL as nucleus. ON has yen for rotary beams and is on 50 and 144 Mc. 1'°PV ia converting BC-459 and BC-696. of the UCENSE MANUAL. To keep WSW and WWM are antenna experimenters, NV hna bugs abreast of amateur regulations, have a on 144 Mc. BUK put rig in cabinet. GTE ia building 100-kc. standard. TUK haa new sixteen-element beam on 420 Mc. copy of the up-to-date UCENSE MAN KA is stuck with 3.85-Mc. 'phone. MQP is building_e_ixteen UA):. in your shack at all times. element beam for 144 Mc. A folded dipole on 14 Mc. and 500 watts from a pair of 813s netted BG V 7 countrieo in 2 hours. MU bro~t hia OBS, OES, and OPS certificateo, took 25c postpaid { no stamps please} ~!~r'.;r ;tst~c. ~~Ta~itiehBtl~;~;:r:.1ecm~ tops the section in traffic and .&nt 7LPA, Arizona, into SCN. THE AMERICAN AAE works 3.5 and 7 Mc. A.KS ia active on SCN. QlW ia Ventura SCN member. VAQ had fun in DX Testa. 7MSG/6 RADIO RELAY LE.AGUE, INC. now is 6MSG. Vertical antenna increaaea night 28-Mc. con tacts for YCZ. CNY is San Luis Obisp_o Club call. MFK is West Hartford, Connecticut busy with OES work at Lancaster. KEI has kw. rig under construction and reports emergency drills for San Fernando Valley. AM has eleven directions available on rhombica for DX work. MEP is on 3,85- and 28-Mc. 'phone JUJ is on /Continued on pa11• 98) 96 These capacitors are identical, elec able to help manufacturers solve an trically. The different case styles unusual mounting or space problem, were, most of them, developed for and cut their capacitor costs by rec specific applications. However, since ommending a unit not normally the capacitors are electrically the thought of for the application. same, it is perfectly practical to use The capacitor that you should use them interchangeably-to use a of course depends on your own prob ballast capacitor on a motor, or a lem. For assistance in any specific motor capacitor with a sign trans case, get in touch with the nearest former. G-E Apparatus Office, or write We have made just such proposals General Electric Company, Pitts at times-and have frequently been field, Massachusetts. ·GENERALfl ELECTR~P, 97 3.5, 7, and 14 Mc. UFH moved to w·2 Land. ASW ia re building. L.A. Metropolitan Radio Club haa__ paaaed the 200 mark in membership. The club meel,11 at Embassy Audi torium on first and third Mondays. FKZ i.s Pl1lll,; GTE, secy. MBA and MBD had 3-way 28-Mc. contact with Chile in which MBA's 30-m,tt mobile rig uutdid Helene's half-kw. MBD has worked 100 countries on 'phone. LS and SPQ formed radio bUBiness partnership. SA haa rhombic• for DX. DA has new ilNLP rotary. AOA cools his bug via 28-Mo 'phone diversion. EAY is up to 90 countries on 14 and 28 Mc. SZY had FB score in c.w. test&.. MLG and DUO > CUSTOMODE REPRODUCER Chicago 99 +a•n•a•n•a•a•a-a• Ft. Worth, is getting hot with traffic handling. NW mal.n• tains activity on 3.85-1\lc. 'phone. No report -Wall received on 144-Mc. activity. While FI.C.l. complaints in Dallas are = = few, the DARC is promoting a cooperative plan between I THE I aruateur, B.C.L. and radio servicemen to improve public relations. Thanks to LGY for sending the one lonely report for this column. Please send along items of interest. Traffic: W5LSN 947, GZU 231, CDU 220, ISD 28, ARK 15, ILZ 13. = = LUY 6. ASA4. I //J I OKLAHOMA- SCM, Bert Weidner, W5HXI - A..,t. SCM, George Bird, 5HGC. SEC: AHT. The ouustanding news of the month Wall the service rendered, by amateur i i radio, to visitors to the Ea11ter Pageant on the Wichita f,adio Mountains near Lawton. The Lawton-Ft. Sill Radio Club had a portable station on the site from S1>turday noon = = until Sunday morning. NGF was in charge until he col lapsed Saturday evening, Traffic from the portable station I /I I was forwarded to Lawton where IGO on 3.5, MDV on 7, and GCM on 14 Mc. relay~d to the .varioll8 nets. Over 700 messages were cleared to OLZ, the Rebel, and other neus. i _A/-,naleur ~ i 'l'?e f?llowingare new members reporting into the 8th Nav~I D1stnct Amateur Net: AIA, AZS, BAR, ERL\: FL, HFX, C C HGC, IGO, !WW, KXD, LFJ, LLY, LTY, 1\, FD, MPV, MRB. NFV is working on A. & M. emergency equipment I fl. I ATJ has new crystals for OLZ and 'phone net. Nl\IN has appointment for CAP. While KDH was looking for another station for emergency work in Pawnee County he contacted KEL, from Cleveland, who was on a boat in the Mediter i eJ..ilrctru i ranean. 'rhe A. & M. College 7050 Club may be heard on Sundays. LTN has modified a 348 until it is almost a fre C d C quency standard. The Kay County Club hopes soon to have mobile contacts with all members. HFW now hat, a brother I I on the air in New Mexico. The 8th Naval QSO Party on 7 Mc. was well attended. IGO reports into TL "K." G VS and C THESE ARE THE PUBLICATIONS .= AQE report luto TL" H." Traffic: W5IGO 443, GCM 254. NMM 198, AST 177, NBD 135, GBS 127, GVS 127, PA I WHICH EVERY AMATEUR 70, AQE 29, IOW 25, LTF 22, FRB 10, ADC 9, GOL 8, EHC 7, ADB 2, EGJ 2. = NEEDS. THEY FORM A COM- C SOUTHERN TEXAS - SCM, Ted Chastain, W5illF PLETE REFERENCE LIBRARY --SEC: BUV. RM: DAA. PAM: EYV. Networks: STEN, I I STTN, STEN (c.w.J. GLS reports from Houston that 144- FOR THE AMATEUR RADIO C Mc. activity is going strong, KFD is running 300 watts. = NQA is on 50, 28, and 144 Mc, ADZ is mobile on 144 Mc. I FIELD; ARE AUTHORITATIVE, I and operates on 14, 28, and 50 Mc. GLS has installed 829B in BC-522 and hat, six-element beam with RC-148 preselec C ACCURATE AND UP-TO-DATE = tor. There are between 55 and 60 active statioll8 on 144 Mc. in the Houston area. IGL, KFY, and MRV are active on Title Price 50 Mc. DAA and SM are co-holders of Gulf Coast 144 Mc. I I DX record, Beaumont to Kingsville. The Corpus C.hristi (jST ...... $3.00 per year* Radio Club recently elected the following officers: LOW, = = pres.; FBC, vice-pres.; AQK, secy.; LOF', treas.; NPA, Operating an Amateur Radio Station - I ac,t. rn,,:r. Active on 144 Mc. are AQK, LOW, EXO, and I Free to members: to others ...... I0c NIF. RQR now has WAS and WAC Certificates. New statioll8 1m 3.85 Mc. are DCP, LOW, MJQ, and IBT. = TheRadioAmatcur;s IIandbook, $2.00** = DAA reports from Kingsville that LUJ and ACL are new I The Log ...... 50c I members of the South Texas Traffic Net. MXV, in Mart, J11 JII lost his antenna poles in high "ind. MJN now is located in How to Recome a Radio Amateur ... 25c is 11111 Houston. NKD has Class A ticket and on :,.85-Mc. 11111 The Radio Amatcur'A License 'phone. LGL is new ORS. Mr. Sparky Barton, editor of STENSCOPE, recently was presented with a new NC-173 I Manual ...... 25c I for outstanding service. Congrats to IU for one year of 100 = Hints & Kinks for the Radio C per cent attendance in net drill. HZJ is active on a.85 Mc. New call in FrceP.ort is OFQ, who holds a 20-w.p.m. Code Amateur ...... 50c I Proficiency Certificate. l\IPE hao recovered from a bs.d I Lightning Calculators: attack of pileumonia. EWZ worked 36 countries during DX Contest. JKB has new three-element wide-spaced beam and C a. Radio (Type A) ..... , .... $1.00 C started working DX the minute he put it up. NIY reports I h. Ohm's La,v (Type B). . . . $1.00 I that, 3.5 Mc.. gave better results than 14 Mc. during the DX JII Contest. Congrata to AOL on the arrival of an 8-lb, 1-oz. A.R.R.L. Antenna Book ...... 50c C jr. operator. PM, ex-DAQ, has new beam and reports 9!1 11111 The Minilog ...... 25c countries. Active on .50 Mc. in San Antonio are: BUV, JLY, VY, LBG, LIV, UB, and AJD. The 144-Mc. gang is I Learning the Radiotelegraph Code .. 25c I BUV, JLY, YV, LBG, and LIV. NFC is active on 144 Mc. C A Course in Radio Fundamentals ... 50c = in Austin. In Seguin FFG is active on 144. Mc. and 3.85 Mc. Will the ECs _please get reports in regularly to the SEC. I * Subscription rate in United States and .Po':18el5- I Traffic: W5MN 219, DAA 83, MXV 81, LWV 12, JPC 9, tll 1-:1ions, $3.00 per year, postpaid; $3.50 in the Dominion Ill ACL 6, GLS 5, EWZ 4, HQR 3. NIY 2. lillf of Canada, $5.00 in all other countrif!s.. Single copies, a.I NEW MEXICO-SOM, Lawrence R. Walsh, W5SMA :15 cents. · I -SEC: ZM. RM: HJF. PAM: FAG. This month the 75 **Postpaid $2.00 - United States., its posseseioni,; Fone Net got off to a fine start with FAG a.o NOS. Those I and Canada. $2.50 elsewhere. Buckrnm bound $3.00. reporting in were ZM, HJF, NXE, and SMA. MYQ just = = missed because of jr, operator troubles. I would like to urge evervone who can put a rig on 3880 kc. to Join the net. Tlie Ume is 8:30 A.M. the 1st and 3rd SundafiYB of the month. The I I Los Alamos Radio Club elected the fo owing: NXE, pres.; NAS, vice-pres. and act. mgr.· MNW secy. and treas. Plano were made for Field Day. The N.M. Bulletin (GQ N.M.) i :J/ie -4-merican i started with a fine first issue. Congratulations. Bob. KAO is now e.c.o. with 500 watta on all bands. NQU will be operating portable on 7 Mc. in Arizona. and California. NQT will be on 3.5, 7, and 14 Mc. from S. New Mexico and j RADIO RELAY LEAGUE i Santa Fe. .TYW is studying with CREI but completed INCORPORATED • WAS. HOX and MBF a.re members of slow speed trunk = • = line on 3545 ko. We would like to welcome OGY to New Mexico. MYA is now on 3.5 and 7 Mo. Barney plano to I WEST HARTFORD 7, CONNECTICUT I handle traffic from Port Bayard. NKG sent in a list of con structive suggestions for net procedure, Appointmenui: =• a•a•a•~-a•a-~-~• = (ContinlUCl on pau• 104) 100 ~~ ....~ .. :-.:{I~;::...,..,,,_ Western Electric is now offering a group of which all Western Electric tubes are noted. miniature tubes, including 2 twin triodes and Data sheets on all these miniatures are avail• 6 pentodes. able for your design files. They were developed by Bell :i'elephone Send the coupon for sheets on the types Laboratories .•. are manufactured by Western you are interested in-or call your Graybar Electric to the high standards of quality tor n.epresentative for full information. HEATER HEATER CURRENT CODE TYPE MAX.PL.All VOLTAGE IN MILLIAMPERES VOLTAGE DISTRIBUTORS: IN THE U.S.A. -Graybar Electric Company. 6AS6 Pentode 6.3 175 180 IN CANADA AND NEWFOUND· 6AK5 Pentode 6.3 175 180 LAND-N orthcrn Electric 6AJ5 Pentode 6.3 175 180 Company, l,td. 5590 Pantoda 6.3 ISO 180 5591 Pentode 6.3 150 180 408A Penlode 20 50 180 r~,;;;;;:;,:-c::=.-- - -Q-:;~- 2(51 Twin Triode 6.3 300 300 1 420 Lexington Ave., New York 17, N. Y. 407A Twin Triode 20 (parallel) 100 (parallel) 300 f Please send me data sheets on the tubes ,irded: 40 (series) 50 (series) 300. 6AS6 6AJ5 5591 2C51 I 6AK5 5590 408A 407A Weorern Electric! ::,.., ____ -QUALITY COUNTS- I AddressCiey ______State----- 101 For COLLINS in New England - order from the RADIO SHACK As exclusive distributors for CoIIins in our New England area, we are prepared to serve your every requirement for the quality equipment bearing this famous name. We stock the complete COLLINS line and can make prompt shipment on all this new apparatus; time payments arranged. TRANSMITTERS 30K 500 watts CW 6 bands 375· watts phone $1450.1 Complete with tub 32V-1 150 watts CW 6 bands 120 watts phone $475.1 Com1>lete with tul EXCITERS 3108-1 20 watt v.f.o. all bands ...... $190.4 3108-3 20 watt v.f.o. all bands with antenna coupling network ...... , 215.1 31 0C-1 80-meter frequency control unit less pwr. sup ...... as., 310C-2 80-meter frequency control unit incl. pwr sup ...... 100.1 70E-8 1600-2000 kc. linear tuning v.f.o • .•...... ••...• 40.1 All exciters complete with tubes. RECEIVER 75A double-conversion, all-band, complete with Catalog• on all Collins equipment free on request. 14 tubes, loudspeaker, pwr. sup ...... $31s.1 HALLICRAFTERS TELEVISION RECEIVER COMPLETE HALLICRAFTER RADIO STATION S·38 RCVR ...... $47.50 HT.17 Xl\lTR ...... 49.50 TOT AL ...... $97.00 Only $9.70 down payment. Model No, £qulpml"n-t N.et Down Ptr M ('.Qde Pric~ Payment for 1% M HALLICIIAFTEIIS t:::ZA !~ •ut ~Jt SX-42 '7S.OO 27.50 21.116 sx.43 1WH)O 18.90 JS.03 s.47 200.00 :ro.oo tS.90 M~9 ,.;-::l~ i~ 21~ c.n, IOM-110.50 20M-115.50. 46\!-SI 1.7S: l!OM-SI HT•l.7 Ut.50 6-1¥,, . :"S3 Hi~1t· 80M ar 40~1-n.SO fl'\io~oo20\I Ql1~&i'1-S7.00 i5~ NATIONAL NC33 IOS.?5 •.59 S.2S NC-46 101 iO 10,74 NCS7 tJ FOUR-20 FOUR-11 rRANSMITTER MODULATOR Ready to go Ready to use WAS $120.00 WAS $72.50 )ur price only Our price only $59,50 $49.50 Complete with. tubes Use it with your and 10-meter coil present rig or your Gives you all-band, crystal-controlled, phone or CW new Four-20. Gives you eleven watts of audio with operation - 80, 40, 20, 11, and 10 meters. less than 5% distortion. You,r chance for even greater savings! Coils for 11-20-40-80 meters ...... each $1.70 Four:20 kit with detailed pictorial instructions for Crystal for Four-20 ( Bliley or Valpey) ...... $2.80 your own assembly ...... only $39.50 For full details on these amazing values in Hammarlund gear, see our advertisement in QST, March. BC-929-A 'SCOPE $12.95 MARKER BEACON RCVR BC-357 $2.95 Thia 3 .. fnch radar-type scope i• readily modified to use as a modulation indicator or a Just the thing for experimenting panadapter. You can run it on 60 cycles by hooking a with radio-controlled devices of all 15 0-watt lamp in series with sorts. Two-tube receiver operates the input to the 400-cycle built-in SPDT relay from modulated power supply. Handy size- 8 x 9 x 14 inches. ComPlete aignals. Includes 2 tubes and relay. with 3CP-1 CR-tube, 2- You couldn't build it for this price. 6H6GT, 2-6SN7GT, and 1 each 6G6G, 6X5GT, and 2X2. Good used condition. Protect your rig with BRAND NEW PER GE SELSYNS PAIR this HEINEMANN s4_95 SC-221 FREQUENCY STANDARD CIRCUIT BREAKER ,;;!•.''. ~de~! for beam position ,. ·. md1cators and many 136.95 other uses. You can run i"unda.mental ranges · these splendid selsyn · control transformers at 25-250 and 2000-4000 ~ :c; stability better 35 volts 60 cycles and han 0.006%. Com- each they'll give yoa permanent, efficient per 1lete with tubes. 10 for formance. rhdnal crystal and alibration charts. $8.50 Jsed but excel- en t working 11-HENRY FILTER CHOKE ·ondition. Better than fuses. Carries Kenyon T-160, starting surges hut trips on brand new; 11 sustained overloads. Resets at henries, 120 ohms TUBE SPECIALS - All brand new! finger touch. Can be tripped resistance, carries EIMAC 304-TH ...... $3.95 ea. manually and used as on-off 300 ma. ; siz.e 4 6 for $28.20 switch. SPST: 4, 15. or 20 x 5 x 6 inches; 807 ...... $ .96 ea. 3 tor $2.60 amp. ratings at 117 volts. mtg. ctrs. 4 8/16 866/866A ...... 75 ea. 6 for 4.10 Specify current. Brand new. x 3 3/16 inches. 3C24/G ...... 49 ea. G for 2.25 Price $2.49. 6C4 ···----·· .15ea. 6AK5 ...... $13.50 SCR-625 Minimum tube order $2.00 HIGH SPEED BLOWER $4.95 MINE DETECTOR \ Ideal for forced Buried pipes, manhole draft cooling; CAPACITOR SPECIALS g,· covers, electric cables, West.inghouse 8 mfd.2000 v.d.c. Iner 1/100 H.P. and other hidden metal 27½-volt d-c teen-filled capacitor. ' Sealed metal objects are easy to lind case has mounting feet. screw termi- /. se,ries motor with this sensitive de drives sirocco nals, porcelain standoff insulators. tector. Works down to Price $2.49 · type blower at about 6 feet. J<'urnished 7000 RPM-we with full set of ran it on 27V Capacitron 2 mfd. 1000 v.c.d. Round can, tubes and bat single-hole mounting, single-terminal style, A C all day te ri es. Good without injury. case common to one side of capacitor. , used condition. ~ Price 29c each 10 for $2.49 ~h BC-746 TUNING UNIT $1.19 7k RIA\ \Dl \HOl to l ·. . Bmnd new. Adaptable use with midget • xmtrs on 80 meters. Con sists of 140 mmfd. variable con- a . denser J coil, and 2 crystals. in case r'I I § \\-\HA\ C IK, ~ only 3'¾, x 2¾ x 1 ¼ inches. CABLE ADDRESS . RADIOSHACK 161 wmnmoK SL BOSlON, !,\ASS .. U.S.A. (Continued .from page 100) MYA, EC. Tratlic: W5NXE 108, ZU 95, HJF 27, HOX 23, KAO 3. MYA2. CANADA MARITIME DIVISION ARITil\1E-SCi\I, A. l\L Crowell, VElDQ-RM: M GL. SEC: FQ. FLASH! The big reunion and banquet will be held over the Labor Day week end at St. John, under the direction of the LCARC. EW is working on new 14-Mc bca.m. NT gave the LCA:RC g&ng_ the dope on the 28-Mc mobile rig. IF' has given Uf the AT-7 for a crystal job. IW piled up nice score in VE Contest. FU has junked the AT-7. Shore Radio Club ofl:icers are: LR, pres.; OY, \ice,pres.; NA, secy.-treas. The HARO booth at the YMCA Hobby Show at Halifax.was a huge succeSII. Ji'Q, on 14-Mc. 'phone and LZ, on 3.5-Mc. c.w., i-.ith T/L operating by HJ using the HARO call of FO, handled traffic as far west as Van couver a.nd Victoria. BC is be.ck on 3.8-Mc. 'phone with low power. FG is be.ck on 3.8 Mc. OD a.nd CR are building 14 and 28-1\fo. beams. DM is on 28 a.nd 14 Mc. JA has new Command set, VFO, and n.f.m. on 3.5 Mc. PX is on 3.8-Mc. THIS IS A REAL XMTR TUBE BUY! 'phone, QR is on 28 l\Ic. EK is going hi,zh power with 829-B. VO6EP has 54 countries from new Q'l'll. RV now ia 3GQ. The TZ40 is without question one of the most versa SP, IR, and PT are active on 14 Mc. DQ finally went VFO tile and useful of all transmitting tubes available ES is working on war surplus generator as supply for his to the amateur today. We have a nice lot of them, S-40 emergency receiver. Traffic: VElFO 54, D(,! 8, FQ 6, armed forces surplus spares, that have never been PX6. used - many still in the original factory cartons. All ONTARIO DIVISION are guaranteed to be brand new and true to rated characteristics. Th•y diuipate 40 watts without cook .. NTARIO -S.CM, David S. Hutchinson, VE3DU - ing, take 7 .5 volts on filament and 1500 volts on O.. Hamilton, Toronto, and Windsor Clubs are making the plate and operate nicely at full power on all great plans for Field Day, BAJ and BOP keep Pa.gwa. on the frequencies up to 60 Mes. Those are a bargain at air. BCP is organizing a net for D.O. T. Radio Range opera tors, 7167 kc., 1\J00 hra. '"QDT" is general call used on the $1.85 each or $3.65 per pair. net, with Pagwa, Nakina, Armstrong, and Earlton repre ACT FAST - All orders subject to prior sale. sented at present. It is hoped to have every airport acroM Canada tied in with this. net ev~ntual!;y· BOP ia new OltS and NI new UPS. AQE 1s working D.21.. on 28-Mc. 'phone. AGC hit the 100 mark in eountries worked on 14-1\lc. c.w. OTHER TUBE BARGAINS ANS can run his 28-Mc. 'phone from the bed. Oflieera of Kingston Club are: GO.,_ pres.; AOtJ, vice-pres.; BBY, AVAILABLE ""!'Y·•trea•.~~a~1d GI, AK~, and B'.J'H, entcrtainme~t com nuttee. BTtt 1B on 14-Mc. c.w. with 100 watts. AXR a.nd GI are trying out 144 Mc. The Brockville Hamfest will be 807 ...... $ .95 ea. $ 1.75 pr. held Jllly 4, 1948. OP bas worked 8 countries on 3.5-Mc. "phone. OPN meets each Sundaf. a.t \l:30 A.M. Thro;Wh the 2.75 pr. ,,fforts of A'l'R, the boy• on OP.l~, QBN, and TL"!' have HY30/3C30 ..... 1.50 ea. been kept busy with traffic this month. Hamilton 144-Mc. 24G ...... 49 ea. .89 pr. net .is working FB. A new club has been formed in Sudbury with the following officers: AXE, pre.s.; BBC1 vice-pre.s.; HY75 ...... 1.05 ea. 1.98 pr. BU~~!~·; a~d A,OG,_.secy. N':w offi~~rs of Wireless Assn. are. 1'.h, pres., Ml', vice-pres., .and IC, secy.-treas. BIF 803 ...... 7 .00 ea. 12.95 pr. worked KH6 on 27 Mc. and AZI, APA, and ATP on3.8-Mc. 'p_ltone. MT worked ,J2AMA and keeps schedule with YE8MB. BQM ia on 14-Mc. 'phone. AUW has new rig with VFO and 811 final. ABP, AQA, BNQ, BMG, BQF, AVK, BIK, CJ, BKR, and BFF ke"J> Hamilton on 28 Mc. along BARGAINS IN OIL CONDENSERS with TG, SP, AQSi BHX, BRS, JU, l'R, ARB, AKW, AYR ·a.nd QU on 4 Mc. QU now has 70 countries and BHX 44. BlK has his cards for 'phone WAC. Traffic: 10 mfd ...... "600 V...... $ .75 ea. VE3ATR 550, A WE 195, 'DU 193, BMG 136, GI 116, AWJ 98, XO 73, BUR 56, EF 50, TM 45, WX 45, DH 27, 2 mfd ...... 1000 V...... 85 ea. VD 26, BOS 25, CP 25, WK 22, KM 16, BOP 14, AFW 5. 4 mfd...... 1000 V •...... 1.05 ea. QUEBEC DIVISION 1 mfd...... 2000 V•...... 1.85 ea. ()UEBEC•······SC!\I, Gordon A. Lynn, VE2GL--Rl\1 6 ~ with only 25 watts, worked VP6CDI and a G on 3.85- mfd ...... 2000 V...... 2.95 ea. Mc. 'phone. TM schedules DL daily. HB and TM had 2 mfd...... 3000 V...... a visit from VE3BIF and moved traffic to BIF's home for 3.45 ea. him. RL worked ON\.G, and Fon 7 Mc. recently. OL has !JO watts to 807 on 3.5-, ,- and 14-Mc. c.w. and recently worked worked J3AAD to ma.ke WAC and his fiftieth country; he SPEaAU MICA CAPACITOR! also has 47 states towards WAS. CA, using n.f.m. during the DX Contest, had 51 contacts in nine hours and is con vinced that n.f.m. is as good as a.m. even during contest conditions. BB schedules LO and W2OUT, and a.iso SSTL .004 mfd ... ·-{2500 w.v.o.c.}$ .39 (slow speed trunk line) on 3545 kc., 7,30 to 8:30 P.M. daily each and invite.s others who may be interested to get in touch 5000 T. V. D. C. with him on the air or by phone. EC maintains several schedules on 3.8-Mc. 'phone. DD is back on 3.8-Mc,_'j>hone. OD a.nd ABJ schedule each other on 50 Mc. a.nd KY "nd Terms: 20% cash with order- Balance C. O. D. If "not ZO are on 144 Mc. XB has AR-6 receiver and is rebuilding in stock" we'll refund by check - not credif slip. rig but maintains schedules with VE3WK daily: at 6:10 A.M. LO reports results on 3.5 Mc. as only fair. BE a.nd SA did good work ha.ndling traffic with Quebec City during the period when all land-line communication was interrupted because over 800 poles were down between Montreal a.nd ELECTRONIC Quebec in the re.cent freezing re.in storm. XX be.a repla.ced 812s in final with TZ40s. VElAQ ia located in Montrea.l a.nd is looking for shack. He still goes home to VE1 Land to MARKETERS .. Inc. work rig some week ends. TA ia heard on 14-Mc. c.w. ABT 190 VARICK ST., NEW YORK 14, N, Y. is on 7-Mc. c.w. He ia only 13 yea.rs old! Trallio: VE2GL 33, BB 29, EC 27, XB 15, TH 11, TM 6. Phone: WAikins 4-4540 (Continutd on pagt 108) •104 Philip Rand started a new trend to real, badly-needed receiver-selectivity with his Q-Ser. Byron Goodman carried it forward with his "Lazy-Man's Q-5er". We applaud both steps, but felt that even more could be attained by special design to really give every ham super-het, new or old, the "New Look" selectivity QST advocates. Our answer is Model 805, l00kc. I.F. Amplifier. Connect it between your last i.f. secondary and your audio volume control and you get a small boost in gain. But what you really get is single-side-band selectivity- a selectivity curve 2.4kc. wide across the fiat top, skirts falling so steeply as to be only 4.7kc. broad 1000 times (60 db.) down, only 7.2kc. wide 10,000 times down! As Byron Goodman says of this new look selectivity, it will "cut thru the QRM and pull out the desired signal like nothing you ever saw or heard". Take Model 805, only 3 718" wide, 4 15/1611 long, 5 5/8" high, make. 6 simple connections to your 455/465 kc. i.f. receiver, (which can usually supply 6.3 V. a.c. at .75 Amps. and 110 to 250 volts d.c. at 25 ma. to the 805) and you have that post-war receiver with the "new look" Model 805 Price, less 1- 6BE6, 1- 6BA6, 1-6C4 tubes, only $18.90 Model 805K-kit complete less tubes, $15.90 703 FREQUENCY MULTIPLIER Model 903 WAVEMETER & 903A FIELD 701 TRANSMITTER, 75 WATT CW, 30 703 Pre-Tune 105 VANALTA DIVISION LBERTA-SCM, W. W. Butehart, VE6LQ-lll\i A has been atnigiding to get beam motor operatin/1;, TA, of H~.'!:.~ visited lldmonton. He kept schedule with hia XYL, .1'.U, from LQ. WB returned to the air with 150-watt 'phone-c.w. rig. MJ patiently a.wait& arrival of African QSL to COJ? W AO Certificate! BW has small compact rig using 81511 m final and modulator. HI has trouble with· B.C.i. KN experiment& with n.f.m. JG has returned to 3.8-Mc, 10 HENRY 300 MA. CHOKE 'phone. AH ia conva.foscing from recent illneaa. CJ is recent We bought a leading manufacturer"s ORS appointee a.t Ra:ymond, BN spent a. few New {not surplus) Tedford 100 KC Crystal, extremely PRAIRIE DIVISION accurate, high activity, shock-Mounted, A NEW LOW ANITOBA- SOM, A. W. Morley, VE4AM - Con PRICED, HIGH QUALITY CRYSTAL, SCHE- $4 9 5 M gratulations to DQ on his fine emergency work for the MATIC INCLUDED, ONLY. • • • .. • • • • • • • .. • Dept. of Mine and Natural Resources. Harry maintained Parts kit, Including 6AK5, sockets, resistors, $1 • 8 O schedules for them when their equipment became un condensers, chassis • ••••••••••••••••••• serviceable. In between time he managed to work the odd bit of DX, snagging V'.ESNA, G3QV, and G2CUL SR and STRUTHERS-DUNN RELAY RP handled emergency me..ssage from Churchill. TM is working on a CPA Net on 7 Mc: and so far has 5DW, 5EM, Control all of your equipment and RE lined up, RO, on hi.a first night <>n 3.5 Mc., worked with this one relay, 1 IO VAC a. ZL and KR. Next night George tried 'phone and came coil, It's the Zenith "Trans-Oceanic"-the unrivalled world-wide Short Wave on 5 individual favorite among discerning sportsmen every bands! The detachable Wavemagnets (U.S. where-as highly prized as a "pet" rod or Patents 2164251 and 2200674) give it this rifle. It plays where other portable radios fail peak performance. Works on long-life battery - in mountains, jungles, on boats, trains, and AC or DC current. So smart you're proud planes. "Tropic Treated" to defeat humidity, to carry it. At Zenith dealers everywhere. radio's greatest enemy. Its amazing power Less batteries $l 24 40* pulls in standard broadcast coast-to-coast plus COPR. 1948 1 ZENITH RADIO CORPORATION * West Coast prices slightly higher. £'-rices snbiect to change tllithout further notice. ZENITH RADIO CORPORATION, CHICAGO 39, ILLINOIS 107 10"-12"-15" TELEVISION ASSEMBLIES • All Major Parts Pre-Wired • Complete with 30 Tubes •12" PM S~••c~ ~di• with DuMont lnputuner - Covers all 13 channels The Champion 11,!odel Telev,s,on Assemblies are completely sub-assembled, complete with 29 tubes plus a CR tube. FM sound supplied with the most advanced circuit, that compares favorably with custom built sets selling for as IO" Kit, No. A-19803 $273.10 much as three times the price. Truly an a..rnazing unit. Quickly and easily assembled with a soldering iron and screw driver No adjustments or aligning $58,62 down -12 months at $20,71 necessary, the unit is pre-tuned. The Picture IF and Sound IF are factory wrred, tested, tuned and tubed ready 12" Kit, No. A-19804 $303.10 for use. Only.the finest components used throughout, Band width of 4.5 me assures perfect picture definition. Step-by-step instructions and schematic $60,62 down - 12 months at $21.42 diagrams ,ncluded 15" Kit, No. A-19805 $393.10 DuMONT INPUTUNER $78.62 down - 12 months at $27,78 The complete front end tuner for Telev1s1on and FM. Tunes continuously from 44 to 216 me without a CABINETS for all Television Assembly Co break. Covers all 13 TV channels and entire FM models are available. Details and prices range. No band switching required for tuning from furnished upon request channel tp channel. TAl Standard Model Television Assemblies are the same high quality sub-assembled units as the Champion Modefs but supplied with a standard front end unit. This front end will handle 13 channels /by band switching, This sensational assembly compares favorably with units selling at more than twice the price, Step-by-step instructions and schematic diagrams included. 10" Kit, No. A-19801 $229.50 • 12" Kit, No. A-19800 $259.50 $45.90 down -12 months al $16.22 • $51.90 dcwn -12 months at $18,34 GUARANTEE-All television assem 15" Kit, No. A-19802 $349 .50 blies are guaranteed to operate to $69.90 down -12 months. at $24.70 your satisfaction when simple direc tions are followed. NEW YORK CHICAGO Offices & Warehouse 323 W. Madison SI. 2.42W55,h5t.,N.Y.19 Chicago 6, Ill, New York City Stores: 115-17 W. 45th St. & 212 Fulton St. 108 .. ALWAYS S,HOP 'NEWARK' F.RST AND -SAVE Build your own SSSR Adapter Smashing Reduction! Unit with this BASIC KIT . HAMMARLUND Basic Components for construction of S_eledable , 513" gle Sideband Re.cepti.on Ad~ptor, patterned from • FS-135-C McLaughlin's arhcle 1n April QST. d T ) for FREQUENCY STANDARD 50 Kc IF TRANSFORMEl!,S (T-I an •2 moderate selectivity. 2 required - $9.00 with type 1898A. Cat. No. 7690. Am Net, per pr. Tube & 50 K IF TRANSFQRMERS IT-I and T-l) for su• $ 6 95 Crystal per s~lectivity. 2 required - $9 00 type t898AX. Cat. No. 7691. Am. Net, per pr.. • (Formerly $14.25) Be Sure You're in Your Band! With this Ft~yC ll"xr) ~~l~o~'?~. ~~~u~l~!,R• t~~-~ ....~:2~.'. $6.0~ unit comply with Sec. 12.135 of the ••• rues. BLILEY MATCHED CRYSTALS (type SRIO). £ Your receiver becomes an accuraCte frrrn;lth m:!Ks crystals mount in single octal tube socket. Frequency All Brand New _ Guaranteed_. omp e e S supplied 405.5 Kc and 505.5 Kc + 0.5 Kc. Frequency tube, 100 Kc Crystal, and instructions. No. •774 difference each pair is 100 Kc + 100 cy $10.80 Cat. No. 9412. Am. Net, per pr...... • COMPLETE KIT of basic components consisltng Lost Coll! of either Two #l898A or Two 1898AX IF Transform• Use Yollr ers One Low Pass Filter #3423, and Two $25 28 CREDIT, M~tched BIiiey SRIO crystals. Cat. No. R-131 • R Tak~ SAVE 143.IJIJ New MILLEN SSSR92105 Single Side band e ONE YEAR on this famous $72.50 ceptor in Stocki Cat. No. A-19407. $75.00 Amateur Net ...... to Pay HAMMARLUND $15 Down - 12 Months at $5.30 Four-11 Modulator Hurry - Only a Few Left! NEW LOW PRICES 1'f~4-~§\(-f:f(•J~ TELEVISION KITS NOW you can get all the Famous Transvlsion TV Kits, Assemblies, and Parts at Prices never before possible; Choose. your Kit and TAKE ONE YEAR TO PAY. List Newark Cat. No. Price Price A-19494 IOBL, 110 Sq. in. pict. TV /FM, cabinet & Ieris incl. 359.00 299.99 A-19495 12BL, 130 sq. in. pict. TV /FM, cabinet & lens incl. 389.00 319.00 A-19505 10" Standard (5 ch.)* ...... ······~····· ·······-····· 225.00 189.00 A-19513 12" Std {with FM)** ...... 296.95 246.00 A-19503 12" Deluxe•n ...... ,..... 359.50 299.00 A-19508 15" Std (with FM)** ...... _...... 372.95 310.00 A-19496 15" Deluxe••• ...... •...... 429.00 365.00 *Television sight and sound only **Television plus FM Radio, 88-108 Mc Regular Price $72.50. Kit includes All ***With lnductuner - 13 TV channels plus FM radio, cont. tuning 50-216 Mc Parts, Materials, Punched Chassis A-24094 All-channel TV-RF Tuner with FM Radio reception Cabinet, Hardware, Tubes and In'. (88-108 Mc) completely wired, with tubes & dial 49.95 41.95 structions. All Genuine Hammarlund Complete Line of Transvision, RCA and other TY Kits and parts ~ith schematic ,1nd parts list. l!se th1S m.odulator with your present components in stock at all th)les! rrg, as a high power speech amplifier or with the Hammarlund Four-20 Xmit While They Last! TUNING UNIT for BC-610 ter. • 11 Watts Audio Output • High 6.3 V FILAMENT TRANS. Impedance Mike Input • 8000 ohm Channel mtg; 2¾" betw. mtg output to match Four-20 • 110 DB ctrs. 6.3V @ 1.2 Amps. Fully Gain • Substantially flat in speech lmpreg. Wire leads. Pri: I IOV range 200-3000 cycles. Drops off sharp ly above and below • lubes: 6SL7GT 1gN'(y ~~.'. ..~::.~...... 88 ¢ {1st and 2nd_ AF). 6C5 (Phase Inver Swell for Hams! Contains 3 ter), 2-7C5LT (PP Power Output) 5U- New Shipment!. midget variable cond. Easily 4G (Rectifier). ' 5 Hy - 200 Ma FILTER CHOKE converted to VFO or ECO Cat. No. S-713, Complete Modulator Built to Navy specs. 85 • basic unit. Externally mounted Kit for 105-120 V, 50/60 cycles. ohms PC resistance. Cera 6AC7, 6L6, 807 used in con• mic standoff insulators. Fully version to make 25.40 watt !~Prbs."".~.~:...... $29 .50 enclosed with 4 ,tud, mtg. xmitter-exciter. Used in BC- Four-I I Modulator, completely assem on I ¾x2V,"1 centers. Excep 610 and Hallicrafters HT4. bled, factory-wired and tested tional quality heavy duty 9x61/4x2"D. Shpg wt 5 lbs. choke. High voltage insu 5 6 .50 .~ ...... f::~i~~.: ...~.:~:~ ...... ·- $49 lation. 3%x41/8x211,"D. Shpg Wgt. 5 lbs. gi!i_y~~~ ... :'.. $1.19 Cat. No. S-595. Special...... $1.49 Send Ord 242 We ers To • N st 55th St Offi(es & Warehouse 323 W. Madison St ew York 19, N. Y.· 242W 55ih St., N.Y 19 Chicago 6. Ill. J)J or I Ch":'· '1_,adiso.n SI 'fo99 6, Ill. . ew York City Stores, 115.17 W 45th St. & 212 Fulton St: 109 Amplifier Instability (Continued from pagd !4) BRINGS YOU THE and suggestions given in the text. Don't use a ~'"I suppressor resistor at the screen. If a similar OF THE YEAR!!! choke in the grid lead of a triode doesn't work, w;e a trap in the plate circuit. 2) In balanced circuits using triodes or audio pentodcs, eliminate the low-frequency parasitic circuit by substituting a 100-ohm resistor for the customary choke in the grid circuit, plate circuit or both. :3) Neutralize tetrodes for reliable stability at the operating frequency. 4) In push-pull amplifiers, balance the excita tion to the two tubes carefully, matching screen currents as the indicator with beam tubes. JlLSt the thing for the SCR-274N and ARC-5 Trans 5) Don't overdrive 807s or other tetrodes. mittet-!'l and other surplus equipment. Tapped at It really isn't too tough. 20 volts, six inch flexible leads. Made by one of the world!s large!-t manufacturers. Dimensions: 3ij" X 3½" X 3~" high. I. A. R. U. News (Continued from pag• :15) national Relations Officer, Union Schweiz Kurz wellen Amateure, Berne (Postbox), Switzcrlaml. NETHERLANDS EAST INDIES The Nederl,andsch-lndische Tlereeniging voor International Radio-Arnatenrisrne is now under going a major postwar reorganization. The head quarters has been relocated at Batavia, where it Use rheostat in primary with this transform.er to was situated before the war. The new headquarters give you perfect 10 volt operation ior 810's, 813's, staff is composed of the following: president, 8005's and other popular 10 volt transmitting tuhes, Beautifully mad!:' and a wonderful buy, Manufac Major F. A. Robextus, PKlFR; vice-presi tured by om~ of th.e w(,dd's largeM manufacturers. Ct•rarnic insulated scrr;,w t~rmlnals. Dimensions; dent, Mr. W. P. Heespelink, PKlXW; secretary, :Jl" x 4'./' x 4~" high. Sgt./Major J. A. v.d. Berg, PKlYL; treasurer, Net Wt. Bl lb. Shpg. Wt. 10 lb. $3• 49 Sgt./Major B. Schapp, PKlBS, and director, Stork No. C-721A Only-~- earh Lt. Comdr. J'. C. Holman, PKlHL. For ~dministrative purposes, Indonesia will be divided into seven districts, PKl through PK7, N.I.V.I.R.A. members in the 2nd, 4th, 5th and 7th districts will be represented by a del egate from each district. PK3 and PK6 will be represented by a district staff. PIG will be di vided into two areas, each having its own dis- trict, staff. ' N.I.V.I.R.A. major objectives are to E'..stablish a strong central society, to rc!lngage in the affairs 20 Volt 9 Ampere Secondary tap~d at 6 volts, Will of the I.A.RU., with particular emphasis on the gtve you 6, 14 or 20 volts. Has numerous applica• Uons inch1ding 12 volt operation of surplus equip• resumption of mutually-advantageous relations ment (14 volts): Transformer for a 12 volt D.C. with its sister societies, to bend every effort to Selenium Rectifier Supply (20volts); Heavy-duty 6- volt F'Hament Transformer, etc. Solder lug ter obtain literature much-needed to effect the re minals. Dimensions: 3¾" x: 3l" x 3½" high. habilitation of Dutch radio amateurs, and to Net Wt. 6 lb. Shpg, Wt. 8 lb. $ l • 95 strive for restoration of amateur radio privileges Stork No. C-~02A Only... each to all PKs. All Transformers are in new, unused condilion, anf For the present, because of the unsettled polit have 115 volt, 60 ryde primaries, At these prim ical situation in the Netherlands East Indies, no you can afford lo lay in several for future use. PKs in Dutch-controlled territory are permitted TERMS: Orders under $3,00, catSh with order. Or· to operate. However, a few amateurs have been ders over $3.00 require 20% deposit, balance COO. permitted to go on the air in central Java and All prices are Net, F.O.B., Dayto~, Ohio., other sections under the control of the Indone sian government. Tha N.I.V.I.R.A. QSL bureau will be estab STANDARD RADIO & ELECTRONIC PRODUCTS CO. lished at Bandoeng, Java, under the management HS l Sw)nd· SL DA"YHHL\ OHlfl, • l l'l. flllton n 1'l of PKlLZ. 110 Gives You. Every Buyi11g Advantage Get Everything You Need from Amateur ·Radio's LEADING .BUYING GUIDE You'll find everything you want in ~eceivers,. trans mitters instruments, parts and station gear in our up-to-the-minute I 72-page Catalog. Get it today. And get every buying :idvantage at ALLIED-spe~dy shipment, money-saving values, top-grade equ1_p ment ideal easy - payment terms, square trade-in deals' and real, down-to-earth help from ALLIED'S staff ~f oldtime Hams. Get the full satisfaction and YOU'LL FIND ALL THE NEW GEAR IN YOUR friendly personal service Amateurs have enjoyed at ALLIED CATALOG - WRITE FOR IT TODAY ALLIED for over 20 years. Be sure to keep your • ALLIED Catalog handy-it's the complete, authori Immediate Delivery on Latest Receivers! tative Amateur Buying Guide. Hallicrafters S-51. ... -.$129.50 National NC 51-...... $ 89.50 Halllcrafters S-53...... 79.50 National NC-173 ...... 189.50 Hallicrafters SX-43. __ 169.50 National NC-183 ...... 269.00 Hallicralters SX-47 ...... 275.00 National NC-33...... 65.9S Save on Carrying Charges Net FOB Chicago. Prices subject lo change without no/ice. Exclusive ALLIED Time Payment Plan - Most Liberal in Radio Get a Square Deal on Trade-Ins Save on carrying charges with ALLIED'S exclusive Easy Payment Plan! You get full refund of carrying charges if you complete payment in 60 days; you get \Vant to make a happy swap? Just step into our Ham 50% refund of carrying charges if you pay in half Shack-or drop a line to Dayton Warner (W9IBC) the required time. Minimum order is only $45- to get a square trade-in deal. Give us the dope, and take up to 12 months to pay. Carrying charges are weo"ll see to it that you get the most for your trade-in only 6% of balance after 20% down payment. No dollar. A good break for you is good business for finance companies-we handle each deal ourselves us. 'Nuffsaid? Check with us before you trade to save you money. No red tape-no delay-you you'll do better at ALLIED. save more onALLIED'S exclusive Easy Payment Plan. THE ALLIED HAM BULLETIN Looking for new dope and really useful "buys"? You'll want to be on the mailing list for our lively Ham Bulletin. It's free-ask for it. I ALLIED RADIO CORP., 0. L. Warner, W91BC I 833 W. Jackson Blvd., Dept. 15-F-8 I Chicago 7, Illinois I CJ Send FREE New ALLIED Catalog I IJ Enter order for ...... I fJ Enclosed$...... lJ Full Payment • Part Payment (Balance C. O. D.) I D Put my name on mailing list for the Allied Ham Bulletin. I I Name...... I NATIONAL ARRL CONVENTION! Address...... I PLACE: Milwaukee, Wisc. TIME: Sept. 4-5-6, 1948. WE'LL BE THERE, Plan to City ...... attend this year. I Zone ...... State...... f ·------111 26 Years Ago (Continued /rom page ,18) tions instantly by the mere turn of a dial." Pro fessor L. A. Hazeltine's Neutrodyne circuit, re cently described, is further noted by G. L. Bidwell's reporting of a talk by the inventor's co worker, Harold Wheeler, as presented before the Washington (D. C.) Radio Club. Mr. Wheeler has given us new circuits for stabilizing r.f. · stages through neutralization. A method of stabilizing the three-circuit regenerative detector by coupling a loading circuit to the grid coil is outlined by L. M. Cockaday, member of the ARRL Advisory Technical Committee and editor of Popular Radio. Kilocycles or meters - ·· how shall we describe the radio waves we are now using? Dr. A. N. ;:;,· 'e Uses two type 6AK5's in wide-bond Goldsmith, secretary of IRE, argues for the for amplifier circuit mer. What say, gang- 1500 .kilocycles or 200 • Self-contained power supply uses sele meters'? nium rectifier Amateurs are responsible for only 5% of the • Covers ALL television channels in use interference to radiophone "broadcast" stations, • Eliminates outdoor antennas in many locations according to a study of the Bureau of Standards • Improves receiver Immunity to off. prepared under the direction of one of its engi channel interference neers, C. M. Jansky. Even with such a clean bill • Simple to Install •------and operate in hand, amateur radio is still agreeable to the Will Wotk on voluntary observance of quiet hours; but not to ANY Television their present unheralded writing-in as law in our Receiver new licenses. Our Board of Direction has pro tested to the Department of Commerce. Two rousing conventions-··• the Third Dis PIC1URE trict's at Baltimore and the Eighth District's at Columbus, Ohio --have contributed much to our ARRL &'Pirit, and where it is impossible for ham 1UBE to meet ham in person, "Signal Report Cards," portrayers of "the friendly spirit of cooperation TYPt ssP4 S'' screen 2:' 5 and good fellowship," are encouraged by QST. "'ith regulor ·s\on use, N•t Random gleanings: The Hoover Cup for 1922 '" tor te\ev• d designed ti Guarani•• , has been formally presented to 2OM, station of N w fu y Jtond e or Above Supplies: F. B. Ostman, Ridgewood, N. J .... The E. T. Transformer f tor filament ot Cunningham Co. announces a new detector Pow er 6 mP• fla· • 6V at o. :t 1.75 am11• for V ,AG amplifier, Type C-299, price $6.50 ..•• Strays ssP4 • 1·5v t·t1er • 1100 puts the blame on vibrator-type battery chargers ment of 1X1-' r<;; ~C at tilter S as a major source of BCI. at 1 ma l1500 7• No. ti Net SO Mc. Wontinued from pau• 50) elevations up to 8000 feet or more intervening, is also worked by the rebound method. Beams are aimed at the highest peak, which is about 10,000 feet above sea level There is some 420-Mc. activity in San Bernardino. W6AOS uses a BC-788 and a converted 522, and W6RSN has a converted 522, a BC-645, and an ASB-5 receiver. Oil City, La. - Louisiana representation on 50 Mc. this year includes W5ML, 50.2 Mc., W5DXB, ,50.35, W5LET, 50.04, W5AEN, 50.01, W5IOP, 50.46, and W5JFF, 50.4. Collierville, Tenn. -'W4HHK says that quite a number of stations are on 144 Mc. in the Memphis area, but no contacts beyond 40 miles or so had been mii.de up to the middle of April. He would like to hear from others within 150 (Continued on page 114) 112 To Have What YOU Need ••• When YOU Want It. • • Tliat 9s OC!B Job Transformers? We are distributors for U.T.C., Kenyon, Stancor, Thordarson and Sola. Terminal can supply transformers for every re- 11uirement ! Steel? Beat the steel sh(!rtage by ordering Par-Metal and Bud chassis, cab inets, racks, panels, etc. from us! Tubes? We carry all numbers of well known brands for receiving, transmitting and industrial use. Check with us for all type num bers of RCA and Eitel-McCullough (Eimac) tubes, also new RCA special long-life Red Tubes (5691, 5692, 5693). what else? All high quality lines of parts and equipment -Terminal is New York's leading distributor of radio and electronic equipment? Prices? Some say you only get what you pay for, but we say you get more for your money at Terminal! Service? Try us and see for yourself - we're all eager beavers! Yes, Terminal is Your Best Bet for Everything in Radio! Distributors of Radio & Electronic Equipment 85 CORTLANDT STREET NEW YORK 7, N. Y. Phone: WOrth 4-3311 miles of Memphis who would be interested in maintaining test schedules. Vertical polarization is in use at present. 8an Diego, Calif. -- The 2--metcr band suffers from an excess of prophets, according to ,V6ZDO. "Conditions poor tonight - no fog - too much RECEIVING and TRANSMITTING TUBES fog - not hot, enough today - not cold enough iito. ·.-.-.-:::::::::: li~ I sn:; tonight - I don't hear W6XXX at hls usual l50Tll Elmac, Net. Price $17. O{TR~tr LOW ::·::::::::::: PRICE .... $9.95 spot - no harmonics from so and so at such 631 7 Pl Strobotron, Net Price $4.50. OUR PRIUE .... $1.79 and such frequency--·- and so on, ad infinitum." MODULATION TRANSFORMER, Stancor A-38,71 Carle says that he has given up trying to tRll List Price $4.50. OUR LOW PRICE $1.49 about conditions by local weather signs as they A, T. R, 12-V INVERTER Model 12RSB often c.ross one up. The thing to do is to get on 11.V DC lnput, 110 V .\C Output, 100 Watts. the air and call and listen, and lceep it up! Oper List Price $44,0u. OUR LOW PRICE ...... $17.60 atip.g from Point Loma, W6ZDO has worked MATCHING SPEAKER W6QUK, San Bernardino, 100 miles; W6DYJ, LS3 Bakersfield, more than 200 miles; and W6BUT ~,'' hea\'y duty PM speaker. and W6PA W in Taft, also about 200 miles Mouutcd weather-proof and distant. W6MFK in Lancaster has been heard. wind-proof acoustically treatt.>d metal cabinet. 4r100-ohm trans• All these stat.ions are on the other side of verv former mounted on speaker, high mountains from San Diego. These contacts · Two-circuit jack on front panel. Our Low $ were made with a converted 522, using 829s in Price . . . . . 5 • 95 place of the 882s. The antenna was a coaxial BUD CABINET RACK RC-1749A dipole mounted on t.he car cowl. Thls is now Black crack.le finished st.eel cabinet, acoommociates two panels, replaced with a 4-element array which can be one 10,%" and one 8¾'." high, hnq.i 18 ?/16" wide. Takes (:hass.is. up to 8½" deep by 15" ,mde. Complete with two used either vcrt,ically or horizontally. 3 5 fiufi"i..~,t ri~Mi · ~-, ...... $ 9.7 s COAXIAL CABLE How's DX? (Continu«l from paue /;//) RG-tl-U-7.5 ohm!'I. Ratl'!d 330 watts in- ,~:'t f(;f put. 400 .Mc. 1 lc per ft...... 9¢ 100-ft~ due time. "Please do not attempt to QSL at per ft. present." . _ ...... -· CM2SW regrets that he'll not RG-59-U- 13 ohml!I. Rated 1.30 watts in- lots of put. 400 Mc. 6c per ft ...... 1000-it.. be able to C!SL hls Contest contacts this year - 5¢ DXCC credit, if necessary, can be obtained from NO. 14 COPPERWELD WIRE Sergio'!{ i;ubrnitted log . _ . _ . _ While operating 0 per 75¢ ritft. Coil iJno~ }:;o<;.t 6 5 ¢ coil /MM, W5LKH ran into thls D4OH feller who has been worrying WlGKM. Rolf would bet hjs 1.¼" PYREX INSULATORS. T;vpc 67017. Isach ...... 89c bottom dollar that D4OH is a Class A pirate 32-FT. MAST AND HALF RHOMBIC ANTENNA . _. _ . _ W 4BA casually worked HKlFQ, HKlDZ Can be use.cl for mounting your own array. Comprises 4 and HKlGH on 14-Me. 'phone not long ago and fl§'rE~\~~!i~d 3t-=~e~~~ew~;!.;~b~rE:~J~tj~g:~ discovered that they are, respectively, father, son 1 band reel; 4 16" galvanized stakes; l instruction booklet. and employee in Barranquilla . _ . _. _ Gadding .\LL YOURS FOR ONLY $8,95 COMPLETE about in Tokyo, W¢EFK picked up word that 15 MAGNAVOX SPEAKER Uncle Sam is putting some of his BC610s to work on other than ham bands now. Most future Js Sensational Value! Wonderful for heaVY duty public address, will probably have to whip up something from auditoriums, theatres, etc. 3.2 lb. parts . __ • _. _ People worrying about ZC6 QSLs Alnico V Magnet. 211 voice coil. can try a new address, Box 4099, Tel Aviv, now Max. 30 watts. Reg. Price $89.S0. the official ZC6 bureau QTH. W3EIV volun OUR LOW PRICE, while $ limited stocks last. • 24 • 95 teered thls information and also claims he couldn't pull a QTH out of PXlA . _. _ . _ When you CERAMIC SOCKET QSL a station who gives you his location and For 826, 829, 832 Tubes. Spring Grip Contacts ..... l9c eaf'.h address, but says he's undercover, you do not put SPECIAL OFFER! TRIPLETT TEST EQUIPMENT anything pertaining to radio on t,he envelope Model 2400. Reg. Net I'rice $49.50. Our Low _Price .• . $35.95 (unlike a few we've seen). Make it look like any Model 2432. Reg. Net Price $8~.50. Our Low Price ... $62.50 Model 3211. Reg. Net Price $63.50. Our Low Price .• . $47,50 thing eLse, a court order, a bill from Macy's, et MINIMUM ORDER $2.00 al . _ . _. _ Via W6AYZ, ex-VU2PB promises a All prices F.O.B. Jamaica, N. Y. Please add postage. QSL to anyone who worked him while he was in Write Dept. Q the Andamans (home QTH in a recent QST) and who hasn't yet received a card . _. _ . _ Yl2AM will not guarantee a QSL to anyone calling him in disregard to a directional CQ. He is also still very much undercover and wants no cards direct . _ : _ . ·- A Jetter to W3DKT from ZC6AA com 92-32 Merrick Road Jamaica 3, N. Y, plains about a lack of radio gear in Palestine. Branch, 71 Murray Street, New York 7, N. Y. Fnfortunately, shipments from Ws have nu imre (Gnntimwl on page f 161 114 Make your Hobby into a Good-Paying Job EARN $3000 to $7500- YEARLY Add the FCC CO.MMF.RCIAL Li WHAT BROADCAST MEN EARN cense to your ham experience and you can fill broadcast jobs that pay $3000 ( Reported by FCC Nalionwide Survey) to $7500 yearly. You know yourself AVERAGE SALARIES If you• ve had any practical that a majority of men in radio elec radio experience, l can train Position Big Stations Little Stations you to pass FCC COM• tronics started their careers as hams. MERCIAL License Exams Get your FCC ticket in a few short Transmitter Engineer $4800 $3000 Studio Engineer $5000 $3650 in a few short wed,s. My weeks by using CIRE simplified train time proven plan can help ing and coaching methods at home in Chief Engineer $7700 $4300 you, too, to make your your spare time. Get the full story by Olher Join Requiring FCC Commercial License hobby into a good paying mailing the coupon right now. Pay Similar Salaries jilb. Mail the coupon below for full details, free of charge, ~:ow. H. GUILFORD it'tL1ill•JII 4•1:• ,,u II I: I'ice President .o"-1 ' CLEVELAND INSTITUTE OF RADIO ELF.CTRONICS ------QT-6 Terminal Tower, Cleveland 13, Ohio I want my FCC COMMERCIAL license. Send FREE booklet, "How to Pass FCC License Examinations," ( does not cover exams for amateur Ucense) as well as sample FCC type exam, and Catalog A showing oppor~ tunity in growing field of radio electronics. Name ...... , •.... ~·-········· ... . A.ddrus . ..••••.•...... •.... ~, •.• , ..•...•...•...... •...... •. ~ .• City ...... •...... Stale ...•. ,.•.•...... •... O Veterana check for enrollment information under G.1. Bill NO OBLIGATION - NO SALESMEN ------~------ THE RADIO AMATEUR'S HANDBOOK The twenty-fifth edition of the Handbook is featured by the complete rewriting of the material to give a more understandable discussion of those basic facts that an amateur should know to get the most out of constructing and using his apparatus. Owners of previous editions will recognize immediately that the over-all plan of the book has been changed - achieving, we believe, the object of segregating the material so that it can be most conveniently used. A great deal of new equipment has been constructed especially for this edition. As always, the object has been to show the best of current technique through equipment designs proved by thorough testing. As the art grows, the problem of presenting a representative selection of gear grows with it - a state of affairs that is reflected in an increase of well over a hundred pages in this edition. New chapters on ultrahigh frequencies, station assembly, and the elimination of inter ference to broadcasting have been added to round out the treatment of all phases of amateur radio. The material on operating has likewise been greatly expanded. Altogether, this revision is the most comprehensive of recent years. PRICE $2.00 - UNITED STATES, ITS POSSESSIONS AND CANADA $2.50 ELSEWHERE • BUCKRAM BOUND $3.00 American Radio Relay League, West Hartford, Conn., U.S. A. 116 route of entry. Active ZC6 stations, who now number ten, will diminish sharply upon the de parture of the British._._._ Joint operation of D4ARA, now discontinued, makes QSLing some what difficult. A former operator of that station, who is now operating D4ATJ, will attempt to confirm all contacts made by himself only as he does not have the complete D4ARA log. So if you worked "Whee" of D4A.RA, QSL to D4ATJ with details • _. _ • _Nope, FE8AB is not a second Cameroons station, it's FQ3AT's new call. WlODU was first with this news . _ . _ . _ A.C4YN has had some new cards printed but is wondering who else is using his call - Reg gets a lot of pasteboards from stations never worked. GD2DF has the same experience. A word to the hallicraft wise: Don't get too close to AC4YN's frequency when calling him. If you have a kw. and a rhom bic on Tibet and can't seem to raise him each time you hear him, better give up. Or else write an apologetic letter to him - you may have slipped up in the past and Reg never forgets a MODEL SX-43 greedy call. Thanks to W7EYS for these words . _. _. _ W6WNI has it that VS4WL is the only currently-active VS4, VS4VR having gone to VSl. ,Jeeves is getting more sarcastic and cynical every day about our inability to work anything south of Key West. Now he's gone back to being an· SWL •···-· covers the pantry walls with QSLs from CM2s verifying his reception. Well, at least we know what a card from there looks like •-·- and there's always the possibility that Jeeves will receive a blank pasteboard some.day which we can fill out to put on the shack wall in order to fool the critics (Type A). Hints and Kinks All the essential amateur frequencies (Continued from page 611) from 540 Kc to 108 Mc ••• ,...... $169.50 mounted at the end of a thin "paddle" made from scrap Masonite. The coil of the oscillator * On Hatry & Young's 20th Anni circuit extends beyond the end of the paddle, to versary, we salute Hallicrafters, a permit its insertion into the field of the coil of custom quality line with precision the circuit being worked on. A "push-to-operate" switch is mounted at the handle end of the paddle, engineering and excellent per so that the power, whlch is obtained from small formance. It's another of "the J:lect external dry cells, is turned on only when a in Electronics" which make H & Y measurement is to be made. The meter, whlch (Continued on paoe I 18) the choice of amateurs throughout Connecticut and Massachusetts. CONNECTICUT HARTFORD NEW LONDON BOSTON 203 ANN STREET 428 BANK STREET 42-44 CORNHILL BRIDGEPORT WATERBURY IAWRENCE 544 E. MAIN STREET 89 CHERRY STREET 639 ESSEX STREET ' NEW HAVEN STAMFORD SPRINGFIELD A handy probe-type grid-dip meter for the v.h.f. man. 77 BROADWAY 97 MAIN STREET 169 SPRING STREET The tnned circuit and the acorn tube arc mounted at one end of the "paddle." 116 AltlllSON HAS IT/ HARRISON HAS IT/ SERVICE THAT JS DIFFERENT- f NOT INDIFFERENT. CAN • Complete Stock! Right here-ready to be shipped. • Service! Prompt personal attention in .our stores. YOU Mail orders shipped within four hour.;. TOP • Lowest Prices! Highest trade-in allowance. THIS? COME IN, WRITE IN, WIRE IN, OR PHONE IN TODAY/ 73, rlJi/ ..J/.arri:Jon, W2AVA THE TOP DYNAMOTOR VALUE TODAY ! FOR THAT MOBILE TRANSMITTER, PA AMPLIFIER OR EMERGENCY RIG C~~~:-~!!a_--;~~liitpJa!\:i~~ti·· 6½" long. (This job won't take up your LIGHT! - only 6¾ lbs. complete. pq~~v~t~!1!t!21Q 1;;·i}\i6nfi~if!~1a3iio ~~~ts at 210 ma; 6 volt input gives ~i~fJriI~~i~~E~~~~le~e~:1,~ S.\~~J\!tr~:~~~t~~iested. original packing. With built in RF hash suppressors ii:.. ~ fJg~~\~~ni~1!~~ $ 8. 95 Send for data sheet giving full performance curves There is no guesswork about HSS ! MONtroR-KEYeR VITAMITE They're all going "bua:s" about this new electron!~ key. Got World's smallest :rechargeable storage your"s yet? Order now! Money back if you waut it (but you battery. Non-spill, plastic case. Shipped won't). dry charged - indefinite shelf life. Flyweh1ht: - only 1 oz. (9/16" x H:" IN NEW Yi?ffl~'HARRISON HAS IT...... $29.95 ~ 117 can be a 0-1 d.c. milliampere movement, is e..x ternal to the unit and is connected in the d.c. now ready for grid return through wires that are taped to the handle. The circuit is shown in Fig. 2. Immediate Delivery A small paper scale is pasted to the front of the bracket that supports the tuning condenser, and THE MELEHAN an approximate frequency calibration is inked in. VALIANT To use the gadget to cheek the resonant fre quency of a tuned drcuit, hold it with its coil • near the circuit in question and tune the dial. At DELIVERED the point of resonance, the grid current indicated PRICE will dip sharply. The unit can also be used to detect the presence of v.h.f. parasitics in low-frequency gear by similar methods. Hold it with its coil near a tuned circuit in which a parasitic is suspected and tune 25% required on all C.O.D. merchandise. through the condenser range. A sharp kick in Calif. purchasers please add 2½% sales tax. grid current will be indicated when the unit is tuned to the spurious frequency. "Truly, the World's Finest Telegraph Key" With the layout and coil dimensions shown, this unit tuned the range between 128 and 160 Me. EXCLUSIVE FEATURES OF THE -- C. Vernon Chambers, WJJEQ MELEHAN VALIANT Correspondence • Automatic dots plus automatic dashes. (Continued from page 67) • Adjustable from fifteen to eighty words mitter to warrant it.CJ being_ mentioned .in maintenance lit erature. Opening uf the h, v. bleeder resistor is also a source per minute. of danger. You may be assured that a new tune-up procedure • Massive base 4 x ½ x 7 inches and is being instituted at W2RVU, at such a time as I am able cradle unit provide solid foundation. to return to the air. Henceforth, the line cord will be dis connected before any operation requiring reaching inside • Purely mechanical in operation, self of the transmitter is performed. As a further precaution, I contained and self-sufficient, no elec intend to use a aborting rod with a long insulated handle to ground the part upon which I have to work prior to touching trical forces being utilized. same. ·-·-Pred Seifert, IV.tRVU Deliveries of this superior instrument have been inter• ------~ rupted because the manufacturer would not substitute infe• Quivira Lake, Kansas rior materials or in any way change the perfected design. Editor, QST: • , . Since I am qualified by now having a long white MELEHAN RADIO PRODUCTS CO. beard, I often shudder when I think of all of the new fellows (and gals) getting tickets without realizing that actually 7061 E. Monroe St., Rt. No. 1 Anaheim, California a ham ticket iil a permit to e.xperiment with lethal machines. Consequently the new ham can purchase a miniature, but just as deadly, electric chair in the form of the component parts of a power supply. The potency is only limited by the funds in his pocket. Frequently remarks are heard t,hat "this power supply can't hurt you much. as it is only 300 volts." F1ew realize that the voltage has little to do with the situation. It de pends entirely upon the resistance of the individual's body - if the resistance of the body is low enough to pass about thirty mils, the lights go out. It is the same old familiar ap plication of Mr. Ohm's. Law. You undoubtedly remember the occUITence many years ago of the lad in an Eastern ex perimental !Ab who was electrocuted by purposely breaking the skin of his wrists, rubbing salt in the wounds and con necting a 22_½-volt 11 B" battery in series with his ·wrists. Even if it was a myth it could have happened. -·• .llexander .Maitland, WiWEF Sweepstakes Results (Continued from _page 65) Founded in 1901 W9NDA 414, W4YNQ ,104, W8HUD 375, RADIO TELEPHONY W7KVU 357, W6QEU 353, W2TUK 391, RADIO TELEGRAPHY W6MLY 383, W9TAK 332, W9RNM 317, Courses ranging in length from 7 to 12 months~ Dormitory accommodations on campus. The colleg-eowus KP.AC, 5 KW W9RBI 314, W4JYB 303, W6IKQ 303, W2RVC broadcast station with 1.1tudios located on campus. New students at:cepted rµ.onthly. If interested in radio training 301, W9KYM 300. necessary to pass F.C.. C. examinations for fin,t.-das~ telr,phone and second-class telegraph licenses, write for details. Club Participation PORT ARTHUR A gavel is offered in each SS to the radio club PORT ARTHUR COLLEGE TEXAS Approved for G.l. training whose members submit the highest aggregate (<.lon!inmd on paqe 1:l!0) 118 HENRY HAS Henry Radio stores in Butler, Missouri and 11240 West Olympic Blvd., Los Angeles, Cali fornia have complete stocks of all Collins amateur equipment for immediate delivery. Also complete stocks of all other amateur re ceivers, transmitters, and parts. I promise you that you, can find nowhere else lower prices, FOR EXAMPLE: more complete stocks, quicker delivery, easier Collins 75A-1 receiver $ 375.00 terms or more generous trade-ins. I give you • Collins 32Y-1 475.00 10-day free trial and 90-day free service. I Collins 30K-1 1450.00 promise that you will be satisfied on every • detail. Write, wire, phone or visit either store • Collins 70E-8 40.00 Collins 31 OC-1 85.00 today. /(J..,. o'lo ~ • Collins 310C-2 100.00 Y wrf,~ • Collins 21 OB-1 190.00 A FEW OF THE ITEMS • Collins 31 OB-3 215.00 WE STOCK ARI! LISTED BELOW • ffallicraflers S38 $ 47.50 • ffallicrafters S53 79.50 ffal/icrafters SX 43 169.50 • COMPLETE STOCKS Hal/icrafters SX42 275.00 • ffal/icrafters S47 200.00 Henry has everything in the ham field. Hal/icraflers S55 119.50 ffal/icraflers S56 99.SO • ffallicrafters T-54 169.50 • Hallicrafters S40A 89.50 QUICK DELIVERY Hallicrafters S$1 129.50 • ffal/icrafters SP44 49.50 • Shipments 4 hours after receipt of or• ffallicroflers HTl8 110.00 Hallicrafters HT9 350.00 • der. Send $5.00 with order and ship• Hammarlund HQl29X 189.15 • Hammarlund SP400X Super Pro 450.00 ment will be made at once C.O.D. National NC-33 65.95 • National NC-57 89.50 National NC-173 179.50 • National NC-183 269.00 • TRADE-INS National HR0-7 279.00 National NC240D 240.00 • You can't beat Bob Henry for trade-ins. National HFS 125.00 • Write, wire or phone today a\Jout your RME HF-10-20 71.00 RME VHF-152A 86.60 • equipment and Bob Henry will make RME DB22A 17.00 • RME-84 98.70 you a better offer than you can get RME-45 198.70 • anywhere else. Meck T60 150.00 • Signal Shifter mode/ EX 99.50 Millen 90800 42.50 • Millen 90881 89.50 • TIME PAYMENT Millen 90281 84.SO • Because Bob Henry finances the terms McMurdo Silver, Gonset, Bud, Sonar, Gordon, • himself you get a better break. Save Amphenol-Mims; we have everything for the • radio amateur. • time and money, deal with Bob Henry Some prices slightly higher on the west • on his personal, profitable time pay• coast. • ment plan. • 11240 Olympic Blvd. Butler, Missouri . LOS ~~~r~:ES 25 C) \' ,. STORES • ,(I HENRY~ RADIO . ' "WORLD'S LARGEST DISTRIBUTORS OF SHORT WAYE RECEIVERS" 119 score. For the past seven years the Frankford Radio Club of Philadelphia has won the award. This year the award goes -yes, you guessed it ...... to Frankford once more! This group of top notch operators are well on the way to realizing their avowed ambition: to win a gavel for each member of the club. Their score this year was 2,670,877, an increase of more than 800,000 points over their 1946 total. Congratulations, Frankford, on a performance that even you may find difficult to improve in the next SS ! The Bloomfield (N.J.) Radio Club obviously means business in the club competition. From seventeenth place in the previous contest, they pulled up to second in this one by scoring 1,438,- 628 points. Potomac Valley Radio Club, a· new comer to the field, earned a well-deserved third place with their 1,149,780. A tabulation listing the standings of the 64 other clubs that entered the competition accompanies this report. Special certificate awards are being made to the leading 'phone and c.w. operators in each club that sub mitted three or more entries. The Fourteenth Sweepstakes was undoubtedly the most keenly competitive activity of its kind in ARRL contest history. It was an activity so replete with new records that one wonders if the contest experts can possibly outdo themselves next November. Time will tell. And, speaking of BIRNBACH RADIO CO., Inc. time, why not take advantage of the summer and 145 HUDSON ST NEW YORK. 13, N. Y early fall months to clean up that VFO signal, perfect your break-in system, improve your an tennas if possible, and otherwise use your in genuity in setting up your station for maximum operating convenience in the 1948 SS? CU in November! SCORES Fourteenth Sweepstakes Contest (Scores are grouped by Divisions and Sections. • • • The operator of the stations first listed in each oection is winner for that section. • , • Asterisks denote stations not entered in contest, reporting to assure that stations they worked get c.redit. • • • The number of stations and number of sections worked by each participant are ,iiven followina: the aoore . . • • Example of listings: W3BES 147,700-844-70, or, final score 147,700, number of stations 844, number of sections 70. 20,425-239-43 .!9,005-181-42 : :: 17,500-200~% 14,910-143-42 !4,338-185-31 13,408-175-31 10W:!5tm=~5 602-171-31 9'993--103-:!9 9:619-133--29 8,~91-119-29 8,497-147-29 f;~~t1gt~~ S,376- 93-23 i:t~t 8¥::~g 3,300- 50-33 2,370- 73-24 800-350- 20-1614-10 72- 17- 6 66- 6- 6 32,572-241-68 ,5,940-100-30 4, 796- 69-28 25- 5- 2 2".J- 10- g 120 GENERAL ELECTRIC FM TUNER bout •t• I. ro"e Cl FM reception reaches a new high in fidelity when this new Model XFM-1 is used in conjunction with any radio While they last receiver or amplifier designed for phono operation. Harvey Special Price. The r-f stage of this translator is unusual in a number of respects. Variable inductance tuning is employed in stead of using a conventional tuning capacitor. This design has two distinct adva_ntages. It provides a highly efficient circuit in our range (88 to 108 mcl which would not be possible with the more conventional methods of tuning and provides drift-free frequency stability. SPECIFICATIONS These specifications prove beyond doubt that this FM tuner excels. CABINET: OPERATING FREQUENCIES: Beautiful hand-rubbed natural walnut, 10',4" high, 11 ½" 88 me to 108 me. 300-ohm input for folded dioolo an deep, 15¾" wide. Tuning dial is slide-rule type, 'wide tenna. Also has built-in antenna. open, with frequencies clearly marked. ELECTRICAL RATING: TUBE COMPLEMENT: Nominal voltage, 110 at 50-60 cycles, 65 watts. Has R-F amp1ifler, 6AG5; Oscillator, 6AK5; Converter, 6AKS; built-in tapped transformer with selector switch for 1st 1-F amplifier, 6SG7; 2nd 1-F amplifier, 6SV7; limiter, voltages, 110 (103-117); 125 (117-133); 150 (140-160); 6SH7i Discriminator and audio amplifier, 6AQ7GT; Rec• 200 (185-213); 225 (213-234); 245 (234-260). tifler, 5Y3GT/G, Dial light Mazda No. 44. The chassis has been tropicalized. The quantity Is llmlte,I and at Harvey's Special Prices are F.O.B. New York Price they won't last long, City and are subject ta Get your order In at once change without notice. to ensure de/Ivery, 103 Wett 43rcl St., New York 18, N. Y. 121 Md.-ntl.-D. C. W2KEL /J6,048-:J76-48 W:JGAU l.27.800-720-71 . W2PVL" aa,345-247-54 Don't Lose those Good QSO's W2ROM ~7,810-258-54 i~i~ m:in=ir~i '\V2SZI, 21,636-:J0Z-36 While Turning Your Beam by Hand W3.TTC 101,440-634-63 W:JOVT W,299-192-53 W3DRD 96,050-565-68 '\V2.RSV 1s.000-200-:m W:ll\ISK 82,240-514-6:l 1.V2PGU l:J,693-261-42 ..alllliiliiJlil"' A W2VXA ll, 770-110-44 MUNGER Sensational ~HJ~,i:, ft~t~8J:g~ W2BTW 9,630-J.07-45 Electro-Beam W3EIS 75,473-522-58 W2BLO 9,450-105-36 Value! W3BVN 71.300-436-70 W2EOY 6, 163- 85-29 W3KZQ 65.753-:190-66 W2SJV ;;.sos-101-z:i W3DKT 61.975-370-67 W2QQ 4,752- 73-:l3 W3AEL 56,963-369-62 W2FYH ·l,526- 73-31 W3MSK 55,688-405-.5,5 W2PEI ,J,004.- 91-22 W3MTQ ,,2.975-411-M W2QHH• ::,4.$8- 47-30 W3GBB &2.613-345-61 W2ZS 2,500- 50-20 W3EYF 51,000-375-68 \V2VNP 2.405- :l7-26 W3JYS 50 ,245-388-02 W2QMS 444~ 19-12 W3HQX H.030-3011-57 W2DUQ* :.125- to- 9 \v:JFYS 4:l.276-:~.50-62 W3LVJ 42.780-276-62 'Phone W3GZH 39.883-301-53 W2PUN !11\,410-1.54-66 peaking up your own PRICED W3BKZ :1S,U6-29l-66 W2PDB 5,656- 91-25 W3HTK 37,365-282-5:l W2WKO 1.360- 34-20 and received signals AT ONLY W3LUL 3:J,360-20H-64 W2RUK 371- 17- 9 W3FDJ ll:l,337-315-53 in a few seconds. Rug W3MOG 27.610-2,,2-44 IV. Pennsvlvanfa W:lJZY 26,500-200-5:, W3GJY 87.425-538-65 gedly built. Powerful W3KZR 25, 732-220-47 W3BKS FXCLUSIVELY BY W3MHW 1,500- 30-20 W:JNWY I 0 794- 41-2:J W3MFJ l.470- 37-i2 W:1LHX 660- ~-~-!~ REX L. MUNGER COMPANY W3NWB/3 616- 2:l-14 ~~~~~.. H~t itrn W3RWJ !4.0- 14- 5 4701 Sheridan Road, Chicago 40, Ill. W3JGK 82!)- 26-13 W3KJM• 40- 5- 4 W3MAX 553- 17-13 W3OMG 4.0- 4- 4 W:.IMPR* 484- 19-13 W:lNAT 2- 1- I W3JQB 8- 2·- 2 'Pb.one '.Pb.one W3KQ.I.T 29.421-235-63 W3~'UV .31,850-245-65 W3AER \/7.192-206-66 W3JVI 6.090- 87-28 W3FIH 18,360-171-54 W3BKK 3.354- 11.5-26 W3MHO 17,226-150-58 W3HO .l ,932- 42-2:{ W:lMUF 14,254-169-42 W30IW 11,250-125-36 W3DZZ 910- 26-14 W31,Q.X W3HWH 608- 22··•16 S,320- 70-38 W3KBX 225- 12- 9 W3LWW 4,200- 88-24 So~ New J er;t;e,71 W20XX l.19,974-o\l&-69 CENTRAL DIVISION W2PWP 108,675-621-70 volt-ohm-milli W2QOM 105,54:J-6.50-65 llUnoir W2JAG 102,938-675-61 W9.FOI t as,345-862-69 ammeter is usually the W2SAI 102.255-602-68 W9ERU 125,960-753-67 W2HEH 101,600-6:J7-64 W91-'JB ll4.240-817-70 first test instrument pur W2IMU 97.262-6:J4-62 W9GRV 106.250-625-68 WYVFIB 105,060-618.-68 chased by any radio ;mf~ ~:i&t:m1:=g~ W9WFS 103.673-604-69 W21'NN 64.900-472-/ifi W9NIT 102,680-60,5-68 man. Chicago Feather W9WEN W2PIN 61,744-4:34-57 !Jl! 0lll3-607-65 W2RDK 60,685-458-53 W9TO 91,040-.569-64 weights offer so great a W2ll.CL 50,700-:J:38-60 W9PNE 86,849-520-{17 W9BGC value in accurate quality, 2 \Vf!GFF ~HitgA~~ ~~l 807 tube •• ,.,u.. UHU,.. 1.35 1 rnfd. 1500V ...... , •••••.•••..••.•..•••••. $ .49 805 tube ...... 4.95 4 mfd. 1!500V , ...... , ••••••• 1,59 Cet Acquainted Offer 24G tube •.•••••••••... .59 BC,458A only a fow lef.,t ... , ...... S.95 New up.to-date giant radio rl"ft'!rPneP map ·--Just right for your control· room wall. A.pproximately 2sux42n. Contains tim" "ones, amateur xones, leading shortwav~ st atl;:•.•L ::;~~~~gT~t:~~n:ND 25c I Please send me: O Globe Champion Data I D Radio Map 0 Globe King Data I D Parts catalogue 0 Globe Trotter Data I Name ...... Call Letters ...... I Address I I ~ity. ~---·;.;.; -~· ;.;.· ~o=·~-.s:t:i;.;·~·~·.,1 .. " ·~· -- ·- - .. .. ·"·' ~ -· --- ... . -• - W9F1N 18,528-19$-48 W9RKP 22.80000-2-51 W9FLH 18,412-152-49 W9FZC 18,013-131--55 W9BPU 18,0,50-143-50 0 17,390-14.'l--47 W9EMJ .16,728-204-41 ~i¼'ba 11,330-103-44 W90TJR 16,125-150-43 W90XP 11,146-125-37 W9ECD W9YMG 8,360-- 88-38 9 tH~tm::t~ W9IQW 7,660- 81-38 ;slWJ 14,742-176-42 W9WXD 7,323-102-29 W9VFZ .!4.560-104-70 W9RH 5,680- 71-40 W9ZST 14,560-182-40 W9li)IZ a,110- sa-2s W9ANY W9LFK 3, 262- 90--29 W9ZOQ W9S1Z 3,163-- 58-22 W9LM rn:g~s=m=i~12,195-136-4.5 W9DR U35- 34-11 W9KPT 11,020-152-29 W9DND 750- 25-16 W9Vl'D 10.579-108~19 W9RLl3 720- 24-1.5 W9JHH 10,424-136-31 W9RRA 700- 21-H W9FQ 9,200- 92-40 W9CFP 675- 23-12 W9EBX 1 W9LED 577-- 21-11 W2BT0/9 t:iit itig Wl)IL:R• 68- 9- 3 W9KXD 8,163- 75-43 W9UJM 60- 6- 5 W9ERX 7,789-101--31 W9FKI* W9NGG M,950-314-70 H~t1It-ti 32,886-263-63 ~8~~ !:Ut ~tjt N 16,002-127-63 W9IBC 4,500- 60-30 13,920-120-58 4,253- 64-27 wgJ 4,624- 68-34 ;it;rai 4,125- 55-30 W9CJO 3,625- 71--20 W9EOL 3,315- 5.1-!!6 W9NVJ 3,115- 45-28 W9MMH 3, 105- 46-27 W9FHTJ 2,964- 57-26 W9CMC 2, 755- 4.8-29 W9HEE 1,932- 4Z-23 Also send for our Booklet on '"Radio W9JSL* 2.~01-- 44-23 W9VHA 225- 10- 9 W9SYZ 2,300-- 50--23 W9QJW 60- 6- 4 Keying and Telegraphy for Begin W9APE 1,633-- 36-23 W9Luc• 32- 4- 4 W9F--ZF 1,254-- 33-19 ners" - W9AA 1,200-- 30-20 W9LP 544-- 23-14 DAKOTA PIVISION W9NMY 540-- 24-12 North Dakota W90EO 468- 20-12 W9FFD 234- 13-- 9 wgHKM 66,930-389-69 This Booklet gives Ilia funda W9Q.FF* 224-- 14-- 8 mentals of keying. • • • It con W9F'KV• 219- 14- 7 ;~ii Ult itt? W9ECJ* 210- 14- 6 Wj!BJG* 1,215- 28-18 tains codes, and how to learn W9QCQ 147-- 12- 7 'Phone them. W90EO 96- s- 6 WfJOZD 35,100-234-6IJ W9UBW 2-- 1- 1 Wi!WFO 5,205- 7Z-35 WiiEGC 4,,36- 74-32 'Phone W9NDA 57,820-414-70 wllYEz soul/I ~'f.~ii-404-!17 W9TAK 4.5,816--332-69 W9RNM 4.3, 1.12--317--68 ;JrJIJ' ~Z:~Atm::~~ W9KLV 10.810-- 92-47 W0GCW 2:l.527-181-52 W9CWP 1 WIIFOQ 19,695-152-52 1ST ABLISHED W9BDV g:~it :t~~ Wi!YJO 19,116-156-49 W9GQB 5,400- 80-27 WilTJVL !1,609-126-47 1192 W9IFA .5, 226- 66-39 Wi!NCV* 11,088-126-44 W9lT 4,070- 55-37 Wl!BLK ll,920- 80-37 W9FVU 3,038- 46-27 1 W9KVD 1,840-- 40-23 ;:~i ·i&t ¥:t:U W9CMC 1,248- 39--16 WIIQVY 72- 6- 6 W9VH 850- 27-17 W9ZYL 850-- 211--17 'Phone W9LXD 560- 29-16 wgrwE 16,748-160-42 W9VFZ 9,158-100-37 MODULATION & DRIVER TRANSFORMERS W9RBY ;l;~~o 8,354- 83-41 W9ZQX m:utu385- 15-11 7,120- 00-32 W9WXT" 126- 9- 7 ;g~~ W90LU 3- 1- 1 W~GLA l:m: ~tit WIIYKY 1,148- 26-18 Mlnn&o1a W9ID CR 107,669--810-67 W9CYTJ C 106,930~1-68 W9DUY W9NH l{li li\:%taaUi W9VDB WilEPJ 32,725-238-55 W9UO W\SVIP 30,366-241-63 W9HUV Wj!KPQ 29,135-201-58 mfG~ ;g}?ft ½~:i~t1it:t~ W9D~ Wi!DUS 13,41~140-4R Wi!DNY 11,500-100-46 ;~8t1! Wi!PIO 8,288- 95-34 ;i~,9 ;~~ i:11~ Ill:~~ W9GF8 Wi!VJB: 3,125- 50-2.~ W98FR W!!OOF* 2,688- 48-28 W9UKT* W9N:&'.M• 'Phone Wi!OWK 27,840-232-60 'I'hone W\lCl3M 23,546-193-61 W9KYM Wl!RVS !!,000-100-32 W9UUN Wi!SZC 7,343- $9-33 These transformers are suit-ible for use with type W9FOO W!!EPJ 520- 16-13 811, 809, TZ40, TZ20, etc. to modulate either triode W9CLF W9BKJ or beam tube RF amplifiers. Two secondaries are W9DCM DELTA PIVISION provided. Impedance ratio primary to secondary W9ll'TL Ar:tan.,a, W9WCE W5LUY 72,270-438-66 number one, 2 to I. Primary to secondary number W9NXM W5JIC 44,713-369-61 two, 16 to I. Will modulate up. to 300 watts input. W9FJI* W5LLU 2i.880-194-48 Modulation transformer, dtiver transformer, circuit ;g~f 3d~~A~i diagrams and other information all for ...... $6.90 W5HDR• 3,444- 63-28 W5BQA 1,063- 25-17 Please include 50 cents for postage and handling. WSEGX* 98- 7- 7 W5LZQ 10- l!- 2 Send full amount to speed delivery and save C.O.D. 'Phone charg,s. Shipped only in the U. S., its possessions and W5LRE 28,490-204-70 C11n11d11. W5FPD 15,000-150-50 Loms(ami ELECTRONIC NAVIGATION, INC. WSKC 114,540-66.S--69 WITTJSN '17,694-568-69 Box 735, Church Street Station W5BUK 51,460-417--62 New York 8, N. Y. W5J3I 20,520-171-48 (Continued on page 1£6) 124 1 , __S_t a_ 1_::-:-~-R;-,v-,0-0 _u_r_ I!. n!, !Rt!J •-v-A-R-,:--;-;-;-~-;-!-;-~-~-E-R-s 8 0 11 5 Volt AC 60 Cycle. Can be used to turn Type 201 115 V. input, 0-135 V. output @ 3.0 small beam antennas, or 0$ indh:ators only. $12,50 Special, per pair ...... $5,95 amps. 0.4 KVA ...... Type 116: mounted; 115 V. input, 0-135 V. output 150 Watt H & H Rheostat, wire wound, 5 @7.5 amps 1.0 KVA ...... • $23,00 Ohms at 5.48 Amps. A Real Buy at .. $1,9 5 Type 116U1 unmounted; 115 V. input, 0-135 V. ) Heinemann Magnetic type drcujt breaker, 5 Amps. Special ...... 95c output@ 7.5 amps 1.0 KVA •••••••• •• $19,00 Filament Transformer; 2.S Volts at S Amps. Type 11261 115 V. inpput, 0-135 V. output@ 15.0 7500 Rms. Brand New •• ...... $2,10 amps 2.0 KVA, ••••••••••••••••••.• • $46.00 Filament Transformer; 2.5 Volts at 10 Amps. Type 12261 230 V. input, tapped at 115 V., 0-270 7500 Rms. Brand New ••••••••••• $2,65 V. output@ 9.0 amps 2.4 KVA ••••••• • $46,00 DYNAMOTOR-5047-D.C. Type 11561 115 V. input, 0-135 V. output @ 45.0 Input 27 volts@ 1.75 amps. Output 285 volts@ 0.75 95c amps 6.1 KVA ...... $118.00 amps. continuous duty rating. Brand New ••••••••• DM-43A DYNAMOTOR SILVERSTAT Manufactured by G.E. New. Input 24 V @ 23 amps. 7500 R~M; outp~t 515/1030/2/8 V.@ 215/260 $2.95 ideal for use as voltage regulator, leaf type, similar in function m,lllamps; faltered. Special. • • • • • • • • • • • • • • • • , to carbon pyle, continuously variable. Resistance 1 0-1200 S~~:~ ';;!-:.. ~'.~~ :~ .b_''.~~~ .c:r:'.''.t.1~~~! :~ .~~'.r.o: $1. 9 5 WIRE WOUND POTENTIOMETER 100,000 ohm, precision made. G.R. type, '' ITEMS YOU MAY BE LOOKING FOR! 1 ~~t'.'_ ~•:. ~ ~.~~t~~·. ~~~~~ $1 •9 5 ·: .::. ::: Selsyn Generator 90 V.A.C. Input 60 cycle. Brand New. ;;w r'·f•.··r.~.·.·•.···.. ·.•,·"•·.·••.· Each ...... ••• $2,50 • . . l 18 .. ;: Choke; henrles at 100 ma ...... $1.25 BEST BUY OF THE MONTH l 10 Volt 1 inch Bull's Eye with dimmer-red •••••••••••• 39c Sprague Radio line Filter, 115 Volt 10 t" . Neon Testers-90-550 Volts ...... 19c Amp; Brand New. Regular $9.75 75c Shielded Phone plugs ••••• , ., ...... 30c list, for Only , ...... • ARC-5 Banana plugs silver plated. Per doz ...... 1 Oc L ... ; De Jur Wire Wound Pots 12 Watt 20,000 Ohm ••••• .... 49c RS-8, Low Loss, Octal Sockets ••••••••••••••••••••••• • 08c WIRE SAG 1/100 Amp. Fuses. Doz ...... • 50c PL,259 Plugs, silver plated •• , ••• , 19c Each. Per 100 $15,00 No. 10, Copper Enamel, 1 00 Ft. Lengths. Each ...... $1.7 5 No. 12, Capper Enamel, 100 Ft. Lengths. Each •••••• • $1,25 No, 14, Copper Enamel, 100 Ft. Lengths. Each ••••••••• 83c VARIABLE CONDENSERS 300 Ohm, Twin Lead Plastic covered, per 100 Ft.. ,•• $2.95 6 Gang Variable Condenser; 1 section 250 mmfd, 4 sections RG-590, 72 Ohm Coaxial Cable. .000035 mmfd; 1 section .00005 mmfd with 5 Air Trimmers 7 c per Ff., per 100 Ft. $6,7 5 15 to 25 mmfd all Silver Plated. Only ...... 9 5c APC-25 Air Trimmers, Screw Driver Adfust. Silver Plated. OIL FILLED CONDENSERS 15c Each. 10 for $1,25 APC-50 Air Trimm'ers, Screw Driver Adfust. Silver Plated. 5 Mfd,, 220VAC, Motor starting condenser •••••••••••• 50c 15c Each. 10 for $1.25 2 Mfd., 600VDC, C.D ...... • 35c 7 Mfd,, 330VAC, G.E...... ,•••• • 98c 10 Mfd,, 600VDC, Capacitron ••••••••••••••••••••• 98c RELAYS O. 1 Mfll., 7500VDC, G.E ...... $1.50 2 x 0, 1 Mfd., 7000VDC, G.E. •..•••••••••••••••• $2.00 G.E.; 2500 Ohm, 4 Ma SPOT, 5 prong plug in type, 1 Mfd,, 5000VDC, Solar ...... $2.95 hermetically sealed. Brand New...... 95c 16 Mfd,, 400VDC, W.E. Co...... •• 98c 2 Mfd,, 10,000VDC, C.D...... • $13,95 Multiple contact, telephone type relays high re sistance. Extra special. • • • • • • • . • • • • • • • • • • 49c 58P1, CR Tubes 5" Green Screen, Brand New, for Only. $1,45 3C24, Triode, 100 Watt Power Output. Brand New. CS-DIFFERENTIAL RELAY 39c Each, 10 for $3.50 832A, Dual Beam Power Tetrode, New ••••••••••••• $2, 15 Dual coil with armature pivoted 3BP1, CR Tubes 3" Green Screen, Brand New ••• .... $1.45 between calls. All contacts nor mally open. Operates 220-250 NATIONAL COMPANY COMPONENTS Volts. 8000 Ohms each coil, con• R.F, CHOKES tacts S.P.D.T. Controls rated 2 Type R-100 in 2.5, S, 1 0 Milliheory sizes Rated at 125 amps. at 110 VAC. Ideally Ma. Each ...... 35c Typo R-300 in 0.5, 1.0, 2.S, 5.0 Millihenry sizes Rated at suited for balanced or bridge 300 Ma. Each ...... 35c type circuits where limited current or power is avail Typo R-15 2,· 4 M.H., 10 ohms. At 600 Ma. Each •• $1.7 5 able. Will withstand 12 G Vibration up to 60 cycles Typo R-154, 1 M.H., 6 Ohms. At 600 Ma. Each •••• $1,7 5 Typo R-175, 22,5 Mlcro Henrie,, 6 Ohms. At 800 Mo at 35,000 feet altitude. 12,500 Volt Breakdown. Each ••••••••••••••••• $2,09 Special low price ...... , • 9 5 C Typo R-33 1, 1 O, SO, 100,750 M. H. at 33 Ma. each •• 35c Typo R-50 in 0.5, 1, 2.5, 10 M.H. cit 50 Ma. Each •••• 35c If not roted 25% with order, balance C. 0. D. All prices F. 0. B. our warehouse New York. No order under $2.00. We ship lo any part of the globe. METERS 0-100 Ma. 2" Round, McCllntock ...... $1,9 5 0• 1 Amp, RF 2" Round, G.E...... $2,45 100 Amp,-6 volt O.C. 3-inch scale, 4½-inch square, gray LEEDS RADIO CO. finish, with 100 Amp. Shunt ...... • ,$2,95 75 Vesey Street Dept. QS6 5•0•5 Amps, D.C. Charge and Discharge 2" Round •••• 69c Cortlandt 7-2612 Now York City 7 126 W5NRR 19,080-160-48 WSUUD* l!- :1- 2 W5RX 15,666-121-52 W8ZLH• a- 1- 1 W5FYS 4,608- 73-32 GET READY FOR THIS SUMMER'S DX W,5HOU 2, 184- 43-26 'Phone W8IDJD 52,066-375-71 'Phone W8PYP 2:l,026-200-68 RECORDS ON 2 METERS WITH A WSGHF i:J,268-123-58 W8NOH 21,932-16Z-55 W5LDH 6,449- 1)6-~,9 W8SLW 1,305- 31-18 W5FMO 6,020- 86-35 W&QBR 1,134- 27-21 W8YMO 144- 9- 8 Musi,stppi 32 ELEMENT BEAM W5LAR 75,600-480-63 Ohta W5BK 62,9:17-503-63 wswz 1:m,288-747-70 weighing only 18 lbs.J amplifies the trans W5WZ 29,760-248-60 129,720-752-69 W/\FGE :!1,168-238-54 ;~I[~is 116,025-720-65 mitted and received power 91 times; price W8l.lWM lll,178-667-68 'Phone W8PNY 87,938-528-67 $60 shipped prepaid. Size, 12 ft. high, 10 ft. W,5IH.P !2,29.6-116-53 WSUJ 80,270-532-68 W5LPG 3,813- 62-25 W8OYr 77,282--464-68 wide. W8BWC 7~.425-434-70 'l'snnestre,e W8PBU 74,025-470-63 W4BAQ. 6:.l,538-3~3-6/i WSZJM 71,600-449-64 Also available in 16 ELEMENTS, weight 9 lbs.; W4RRN 63,181-477-67 WS!JZ,T 68,827-49:J-57 power gain over a folded dipole is 40, price is W4HOJ ,59,590-378-,59 W8VTF 68,400-457-60 W4Kli 54,300-455--60 W8NZI 66,938-425-6:l $35 shipped prepaid. 8 el. weighs 4 lbs. $20. WHQ_Y 49,158-37'!-,53 W8LFE 65,000-500-65 W4.r.rn ,t;J, 717-302-118 W8TKS 62,152-461-68 W4ITY 27,981.-204-55 W8YPT 58,789-389-61 THE OWNER OF ONE OF THESE BEAMS HAS AL• W4CVM lll.958-la3-51. WSDAE 54,739-411-67 READY WORKED YARMOUTH, NOVA SCOTIA, W4.FLW [2,900-130-5o W8SUZ 54,060-409-53 W4GX J 1.840-128-37 W8 m r,1, 940-425-49 FROM NEW YORK IN APRIL THIS YEAR, ON 2 W4BOR HJ,868-104-4.2 B 49,088-428-59 METERS! W4RQW* 9,806-116-3,5 F 48,000-300-64 W4MRD 7,863- 93-34 44,22,5-290-61 W8ZAP 41,063-330-50 'Phone W8WE 40,382-331-61 Complete line of 3, 4, and •5 element ten meter beams, W4AQR 32,160-240-67 W8OUR 37,194-271-M W4FIS 29,440-2:14-64 W8UZF 35,187-2R2--50 WIDE-SPACED, PRE-TUNED, PRE-MATCHED. A Super W4TWI 9,824-154-32 W8I,:BJ M,200-300-57 OX 8 Element Ten Meter Beam power gain of 20; and W4JMZ* 308- 14-11 W8TAQ :12,450-230-59 WRTAJ 30,895--242-4.9 a 3 Element 20 Meter Beam, wide -,;paced. 29,950-30:J-50 ;~jK'! 27,272-246-56 NO TUNING TO DO ON ANY OF THESE BEAMSI GREAT LAKES W8AL 2,5,803-21:Hll DIVISION W8UMR 22,663-18,';-49 JUST PUT UP AND USE! Kentua/q/ W8YJE 24,970-229-44 WB.EXI 21,840-336-65 Send for literature W4KVX tal,655--786-67 W8ZCD 20,680-257-40 W4ZWR 69, 120-4.32-64 WRDQC 19, 712-176-56 W4P1lJ fl:i,800-440-,58 WRTYX 18,670-172-44 W40MW 2:l,4:lS--218-43 WSYGR 18,600-155--48 U.H.F. RESONATOR CO. W4UXH 10 JJ00-100-40 WSPBX 18,407-201-37 GUION ROAD RYE, N. Y. W9BP8/4 W8NMR 17,580-149-46 W4FQQ :rm:: ~~j~ W8ZNQ !5,910-149-43 W. F. HOISINGTON, W2BAV WSWAB l:l,.519-155-35 'Phone W8AZU 12,880-140-46 W4YNQ 54,805--404-68 W8PYX: l0,760-140-40 W4.TNU 5,217- 72-3"6 W8RFA .10,633-11.0-49 W4JYS 6:J0- 21-12 WRNPF 10,631- 9,5-45 W4JBW• 6:l0- 21-12 W8TJNA l0,140-104-39 W4IYR 416- 16-13 w y 10,046- 86-47 D ll,400-l 19-32 BC.t\J!,~!!'!a~!~!:O.INC. Mlchfpan JM 11,939- 81-38 in all technical phases of W8SOW 75.518-620-61 .s;200-1on-41 WSRRP 75.442-564-67 W$TNB 7,711-100-31 RADIO and TELEVISION W8URM 6:l,865-448-57 W8VQI 5,135- 79-26 W8GQB 55,692-444-63 WEEKLY RATES DAYS-EVENINGS WSZFK 4,244- 73-29 W8GP " 47,857-356-54 W8KJK :l,188- 51-25 1 W8YDR 42,627-289-09 W8fJWP l,813- 30-25 VETERANS: :;Se!nt t'iiti• o•n'i~I-.~! W8FJL 42,250-261-6,5 W8VDF l,040- 26-IR For Free Cataloc write Dept. ST-48 W88AY 41,640-347-60 wswwu 720- 20-18 RCA INSTITUTES, INC. WST.RN 41,5:JB-354-,59 WSODZ 660- 22-12 A. Serolee of Radio Corporation of America WSAR.T 41,250-:100-55 WRBC,T 420- 15-14 350 West 4th St.~ New York 14. N. Y. WSONR' !12,302--219-,59 W8J,1KK* 19:l- l!l- 8 W8.FXR ;U,238-256-49 W8THJ 1.54- 11- 7 WSUAS 28,620-212--54 W8UQR 24,200-220-44 'Phone W8UNK 22,771-204-45 W8TRX :rn,488-2aa-a2 MAKES SENDING A PLEASURE W8G8J 20,570-187-44 W8S.DD 31,626-251-63 WRBIU J9,584-l50-.~3 W8BKP :H,240-221-71 GENUINE IMP!lOVED DELUXE W8CHJ 18.018-234-:W The Bug W8PXP 30,13:l-243-62 ONLY W8HP 1.5.610-137-57 IVRNCV 15,950-140-58 with Patented W8IXJ 14,550-194-,10 l 1,83:l-ll 6-51 JEWEL VIBROPLEX ·wsuE 12,444-rn:i-34 ~mt.rcw f1,:l40-105-54 Movement W8SWA l0,950-146-30 W8KUW 9, 180-103--4/1 W8DM I0,260-ll4-36 \\'8ill'tl,' 7,247-112--26 W8YY 5,928- 81-39 W8NDN 1, 176- 77-46 ''Original" W8ZSN/8 5,54/l- 82--29 W8ATK 2,530- 55--2•~ WSY.FQ 5.063- 8:l-2S W8JJM 2,-196- ;19-32 Deluxe Model WRFX 4.313- 75-23 WRFlJ,R 2,376- 44-27 Illustrated W8M<1Q :l,792- 79-24 W1!QB.F 1,568- 33-19 WEUWO S,oJ4- 79-19 W8PNJ 1,1s4- :n-rn W8Rfll 3,190- .58-22 W8EQN* l,064- 38-14 W8CDQ 3,098-- 60-2l WSTYM 828- 2;1-18 W8VZ'L 11,060- ol-\14 WSBDA 650- 20-13 W8A.IB 2, 7 50- ,55-20 W8QQ 158- 9- 7 ONLY W8WDV 2.575- 52-25 W8WOV 2,4Q0- 50-24 \VSCLL 2,200- .50-22 HUDSON DIVISION $19.50 W8BM.F 1,853- 39-19 W8VMC !.,700- 49-14 I!!~ New -York No special Nkill r~quired. No tirin11, arm dfort. Just pres!'! 11:"ver - W8ZHO 1,4,52- ll6-Z2 \'ibroplex do~s tfw n'st. It's thf' Patented Jowef WSLSF 1,1ao- 28-17 ;~t~b ii:~ggj~g:gg Mo1·emcnt fec1turc> th.it hat> cut ~ei:iding l:'ffort in W2DTJ 47,212-408-58 1 ;m;i rn~ jtrn W2KNR 37,950-330-46 ~~![ai1:~e i.~1;.1/i~,l~h: {t.S, 1~;~u\~·br~t;1~te~1st~h~ WRZBU 858- 2,5-14 W2N'RW 31,875-2,50-51 j1•wt-ls in the tlnest-ma ANTENNAS PANEL (A) Sma II four >ection telescopic METERS 110 VOLT aerial ideal for All Brand New and Guaranteed portable- receiv er'$, transceivers GE 2" Round 0-500 D.C.-M.A .... 2.97 SUPERHETERODYNE RECEIVER or fest equipment. Simpson 2" Round 0-15 D.C.-V...... 2.97 This Crystal fixed frequency receiver comes with Triplett 2" Square 0-40 D.C.-V ...... 2.97 full conversion instructions for variable tuning of all 99¢ Sun 2" Round 0-300 D.C.-V ...... 2.97 ham bands and broadcasts. A highly $elective iuperhet receiver, 110 V A.C.powersupply, built-in. GE 3" Square 0-150 A.C.-V ...... 3.49 VseJ the following tubes: 6K7-R.F. Amplifier, 6K8-dual purpose mixer (B) 22" tapered and oscillator, 6K7-1.F. Amplifier, 6C8-detector, high frequency 6C8-Output, 6SN7-8.F.O., SO-Rectifier. Dimen aerial covering 'iions-3½ X 19 x 11 ½ inches. Comes complete, A 150 to 200 MC. brand new, with one set of coils and $ l 6 S · ldeaJ for mobile two sets of tubes...... • 9 or fixed station B. use. 'UN RADIO • TERMS: All items F.O.B., Washington, 0. C, OF' WASHINGTON, D. C. All orders $30.00 or fess, c:ash with order. Above $2.69 $30.00, 25 per cent with order, balance C,O,D. · 938 f STREIT, H. W, WASH. 4. D. C. Foreign orders cash with orders, plus exchange. 127 WlHJP/2 .5,082-- ,7-33 W2SVX 36,190~142--44 W2CFY 2,464- 4:l-28 W'2BTG '15, 713-304-59 W2WQll* 8- :il···· ;l W2DQH 32 832-259-64 W2BLS :n:110-254- 61 N. Y. O. & l,, l. W2TUD 30,840-257-60 W2IOP 156,555-882--71 W2DEN 29,07$-247-47 W2AYJ 108,150--618-70 W20AE 27,625--224--50 W2PZE/2 82,045--541--61 W2JHE 26,982-250-43 W2HMJ 77,824-608-64 W2JME 2,5, 172--203-62 W2KIR 63,619-398--65 W20MS 2:l,664-207-58 W2NCG 61,360-416-59 W2NIY 23,418--247-38 W2TYU 59,400-550-54 W2'1'ZX :/3,200-160-58 W2GTL .51,544-380-68 W2RYN :J:J,860-254-36 W2WC 50,050-308-65 W20HN 22,605--207-44 W2CQB 20,518-236-35 ;~~~ t1/.~it1itix W2AQG 18,383-201-38 W'lD XL 45,220-323-56 W2YPI 17,515-226-31 W2MDM ,U,328-370-56 W2BNU 16,236-198-41 W2LRI 40,837-371-45 W2LMO 16,080-201-3!! W2DZA 14,700-148-50 ~Xbo !~:~~t:i5i:~g W2PGX 14,202-150-38 W2QBS !l'l,778-329-46 W21TD 12,926-14.2-46 W2IFA :36, 240-61 ~A00/2 12,210-II 1-44 W2QYZ !{5 346-41 ,'l2MDP 11,701-127-37 W20RZ 35 266-66 W.2GNW 10,044-167-31 W2JBP 34 276-ll!l W20CC 8,625-150-23 W2A WF ' 28!-1-60 W2DCP 8,500-100-34 W20WX 31)8--4:l W200 8,100-120-27 W2ZV 219-60 W2EUV 7,758--107-29 W2LPJ 276-47 W2UIG 7,580- 90-39 W2KJU 262-63 W2ASY 6,8,51- 95-29 W2KKR ,i, 350-45 W2JC 6,748-137-27 W2PLR 24, 153-64 W2BXY 6,500-100-28 W2RGS 6,250-100-25 t]M8 ~~:2a2->]Wtii W20YD 6,000- 80-30 New Direct Reading Wattmeter. W2NWK 20,553-202--51 W2WEO 5, 775-101}-i:l W2M.JO !9,516-2:J8-41 W2QJY 5,265-- 78-27 W2LQP 19,440-180-36 W2ANW 4,876-105--23 Micro-Match MM-252 or MM-272 continuously W20BU 19,393-226-4:J 12 3,910- 87-23 monitors RF power and SWR up to 500 watts. W4LOM/2 19,378-170-46 Th'.~lrfR 3,744- 5~32 W2A.JI: 19,344-204-48 W2GQR :,,680- 64-23 $60,00. W2UGV 18,840-24.6-32 W2CFW 2,970- 54-22 W2Clf'.X 2,280- 38-10 Other Micro-Match models available for opera. ;~mi. rn:iitMs=i~ W21PJ l, 750- 35--20 W2GGN 1.5,557-166-47 W2ISV" 1,575- 85-18 tlon at 500 KCS to 250 MCS and power levels of W2OUT l:l,756-18Hl8 W2CPJ 1,485- 33-18 2 to 50,000 watts. W2MOU .!3,497-205--33 W2JTM 660- 24-11 2 W2tJGL 488- 20-10 H:23A=½M:j~ W21IN 384- 16-12 ;~mvW2UAL U,250-150--30 W2UJX* 260- 13-10 M. C. JONES ELECTRONICS CO. W2CUQ 9,600- 96-50 W2NZC 160- 21- 4 W2BQO 9,440-118-32 120- 9- 6 P.:O. Sox 1519 KY 4AJ,'/2 8, 100-163-20 ;i$~~ 75- 6- 5 W2PRE 7,483- 74-41 BRISTOL, CONNECTICUT W2BO 7,400-100-37 'Phone W20BY 6,5$8-122-27 W2RVC 38,464'-301-114 W2KVL 6,468-100-26 W2JKH 31,491-207-61 W2DBI 5,735-- 62--37 W2MLM 19,910-182-55 W2WGZ 5,355-- 77-28 16,335-182-45 ;~g~ 15,015-120-52 W2K.'l',ll' 5,340- 8il-:JO W2KHK 14,364-126-57 2 W2PCX 7,310- 86-34 RADIO ~~fti~ i1:i~g: ?tii W2CCS •l,572- 64-36 W21WP 3.045-- 42-29 W2XKK 4,354- 65--27 TECHNICIAN and RADIO SERVICE COURSES W2CBS ll,176- 68-16 W2FDL 3,400- 50-34 W2AWR 2,160- 36-24 W2MGF :1,100- .55--29 FM and TELEVISION ;~~t 1:ii:t i!l:rA W2.KMK 1,836- 51-18 Approved under !he G. I. Bill of Rights W2ETL 1,094- 31>-25 W2ESC 1,500- 38-20 W2LGK 825-- 28-12 W2UWK 6,50- lH-13 AMERICAN RADIO INSTITUTE W2IBE .564- 24-12 IOI West 63rd St,, New Yorlc 23, New Yorlc W2HBO 475- HH.O W2NQR 144- 9- 8 MIDWEST DIVISION TEACHING RADIO SINCE 1935 W2RUK 10- 2- 2 W'JRTZ* 8- 2- 2 Ioua W2PW.J* 2- 1- l 71,890-593-6.5 'Phone iHgtiitg§ W2TUK 40,078-3Ul-4\ W2EGG 35,979-271-67 1::m=i~t~!i ~l,560-180-56 31,959-303-53 ;~~i~) 17,496-163-54 ~l.444-183-47 W2SKE 8,405--103-41 17, 444-178-49 W2NNH 1,700- S4-20 lS,125--121-50 W2KZE 1,050- 30-14 14,053-148-47 w2vou• 1,050- 35-15 l.2,540-1111-44 W2MBU 472- 59- 4 5,503- 71-31 W2NHR 413- 11>-ll 3,600- 50-36 W2IAW 290- 11,-10 1,013- 27-15 398-11 BROADWAY, NEW YORK 13, N. Y. W2RQJ* 2- 1- I 87,5-- 27-14 180- 12- 6 No. New Jer8eV 166- 10- 7 W2BXA l.l.5,575--674-69 94- 8- 5 W2CZO 107,640-626--69 23- :i-:i W2CWE 9:l,537-537-70 'Phone HEADQUARTERS Wz~~~ ~&:~it.iit~~ Wll,JKT 2.Z.... 3- 3 W2ANG 80,080-616-65 Wjl'l'FM 10- 2- 2 for W.2LTP 79,902-586--69 W2LJR 78,708-370-66 WI\BQJ Kansa, W2BBK 78,325-60~-65 W!!DYX 108,306-666-65 W2TNA 66,836-510-62 ,.,~DAE, 13j:aI3j1Ji~ W2CWK 64,488-470-5.5 W0A.WP 78,795-4.64-68 W2TSL 61,640-460-1\7 WBBDU 62,075-383-65 ;rnfil :&:gii:1A~1 W0DEP 57,300-382-60 W2DRV 50,188-4.02-50 W0SIL Sl,972-U2-58 * * * W2JIB 49,560-336-59 WWlfTO¾~• !?1,550-1$0-58 AMATEUR EQUIPMENT W2HZY 4$.,760-314-62 0 = !4,670-163-45 W20ST 48,594--342-57 Wl!A.GO 11, 150-114-40 W2LFR HAM RELAYS FOR EFFICIENCY, CONVENIENCE, SAFETY • For SPDT switching 52 to iS ohm coax cable ••• handles 880 watts of rf powf'r at 100 me. (limited only by the rating of the cable connectors). % 11 pure silver internal contacts easily reached by handy inspection port.. 3/16"purc silver external contacts ( DPDT) for indicator lights or other a,:;sociated circuits. Coil voltages up t? 440 VAC or up to 120 VDC. Series 7200 (AC) or Series 8200 (DC) ..• Net price to hams $7.50 ••• with aux. contacts $9.30 • For filament protection •••• Prevent appli<'ation of HV until valuable tubes are warmed up. Easily adjustable from 10 sec. to 1 min. For clean make. and break, contacts a.re ¼" pul"e silver. Available SPST to DPOT. Alt single throw models f"ithcr normally open or closed. Treat those high pri,<'c>d bottles rii;:ht and increase their life. This fine rn relay wilt pay for itself over and over in the yean1 to come.Serles 300 .•• net price to hams $4.95 or $5.10 • For overload protection ..... Don't ll't accidental overloads flatten your tubes. 'VVhy not eliminate this worry once and for all with a fast acting OL relay. !it' silver D PST contacts break circuit auto matically if current exceeds any predct('rmined value between l50 & 500 mills (type 700A), or 500 & 1000 milts (type 700B). Contacts re-ad mechan ically. Net price to hams •.. $6.09 See your lobber today. Be fully equipped for max imum etficieni;y, convenience, and safety. Thl'::'re is an Advance relay for every ham need. Valuable, complete catalog available at your jobber's or sent fr~ 1260 W. Second Street, Los Angeles ·26, Calif. 129 WIHY ,!,780- 54,-.i8 W0LLN WlEMG 3,680- 64-23 W0VEE WIPLJ 3,025-- 56-22 W0YKR WlQJB 1 FOR 2, 6, 10 and 11 METERS W0PWV WlAJ :i:~~t m:=J~ W0KCG W!QF'O 1,370- 35-16 WlJDP 99\l- 33-15 THE RME ~S&jl:; WlQQH 940- 24-16 W0ZZW WlJ'CK 870- 29-15 W0KTK WlPLU 605- 24-11 VHF-152 W0KHD WlOBN 575-- 23-10 WIMKZ 51)()- 20-12 CONVERTER 'Phone WlLNX 4.67- .!7-11 W00MG :!8.080-299-64 WlHJ 442- 18--13 WllDEA U,400-115--50 WlKWU ·132- 18-12 • • • 1,584- 33-24 FOR IMAGELESS W0BVL WlNZB 23- 3- 3 NeJJraska 'Phone RECEPTION W0DNW 103,515--620-67 WlJN:X: 26, 460-223-60 WllQNP :!5,910-2!16-54 WlPRV 211,75U-.!66-50 • • • WllF'WW 22,064-197-56 Wlh."'I'E 12,446-127-49 A "Must" If Your W0ZOQ 1,654- :12-21 WlPAW 10,680-100-44 W0INR W8- 21-19 WlPQY 9,520-124-32 Receiver Only 'Pb.one WlPLK 7,124- 87-42 WllRQK !lO 656-241-64 WlNBI fl, 432-101-32 Tunes to 18 MC. W~GDB 1.3)50-126-5.5 WHIM r,, 974-103-29 863- 23-15 WIAAR 1,696- 53-.~2 Wi!ZDV WlOTH 1,520- 35-19 WlNYO FEATURES: WlOMI Utt U:ff NEW ENGLAND WIN.KW 1,237- 33-15 Image Rejection Ratio Of All-Gear Planetary Tun DIVISION WlNBL l,054- 31-17 Apprax. 54 db. ing Mechanism Connecticut WlIFR 1,026- 27-19 Provision For 4 Separate WIRY 121,958--70&-69 WlPCO 420- 22-10 Each Band Calibrated To WlBIH 105,225,613-69 WlPVW 405-- 18-- 9 Antenna Connections WlNMP 85,231-528-65 WlJ"DP 113- 9- 5 Cover Full Sweep of WlMTR 45,060-377-48 WlLCF" 63- 5- 5 Miniature Tubes For WlCA U,745--253-66 WHLS 28- 18- l Sensitivity & Low Noise 7" Dia. Scafe WlLHE 40,625--325--50 WIFRV 6- 3- 3 WJGVK 3.5,lU0-272-52 WlMCR 3- 1- 1 Temp. Stabilized Osc. Self-contained Power WlOJM :!2,465--305-43 Circuits Supply WlIC 31,514-287-44 W~ ~vassachusetts WlQAK 26.94.5-262-41 WLTYH 95,366'630--63 WlHV 17,500-126-.56 WlEOH 83,400-484-69 TWO MODELS: To match in size the WlMHF 17,325-266-33 WlKJO 67,283-425-64 WlFX.l:l 1.5,120-128--48 WlBKG 19,552-208--47 RME 84 or the RME 45 WlMCI 14,820-124-48 WlQIS II ,354-1 52-31 ;u11 u:m:12ctii WlBHM 9,504-132-:16 WlMUN 14,526-136-54 WlDJC 6,816-107-82 WlKDW 13,240-192-27 CENTRAL RADIO PARTS CO. WlJMI 4,608- 72-16 \VlAZW 12,023- 92-53 WIAPA :l,375- 50-27 Wl,IUY 7,470-125--24 1723 W. Fond Du Lac Ave., Milwaukee 5, Wisconsin WlLKF H.:349- 71-19 WlJLT 7,:no- 85-43 WlIJO :J,094- 50-25 WlKOS 4,750- 76-25 Wendell Ciganek• W9SYT WIEFW 1,880- 47-16 WlBEF 3,064- 65--19 WITS• 93,113-573-65 WIBVR 810- :.!7-15 WlFTX' ~.502-475--66 WlBDV 650- 20-13 WlVGi H,603-.314-57 WlOPJ 600- 62- 4 WlDX• WlMOK 91- 7- 7 WlINF• ?ii::t38j1tiij~ WlLLN 70- 7- 5 WlMUW• ~0.000-200-40 WlBBL 2-- 1- l WANTED! WlDF• 15,675--110-57 WlPEK• 5,771-100-29 'Phone Western Electric vacuum tubes. Types I0IF, l02F, WlFWH• 4,270- 62-28 WlWL 2$,068--213-68 WlBDI• 3,939- 51-39 WlCOI 8,064,-. 84-4.8 272A, 274A or B, 310A, or B, 31 IA, 313C, 323A, W1UN1 ,550- 20-11 WlOMJ 539- 25-11 WlLVQ• :J5- ·1-- 4 1 885- 14-11 328A,329A,348A,349A,352A,373A,374A,393A, ~tiw 38- f>-- 3 394A, 121A Ballast Lamps. 'Phone WlBDV 3- 1- I WlATE :!7,672-283-68 WlLBZ 2- 1- 1 Box 110 • QST WlON 10,340-111-47 WlMRP 8,750-125-3.5 wrnJ""' Hai¥:f.~ifi45l-65 Maine WlIJB . 65,520-585-S6 WlGKJ 68,660-419-56 W!AVJ 60,984-484-63 W!HUL 51,750-414-50 WICRW 49,ll75-400-50 WlNXX WlAOQ 47.722-303-63 WlDEO t:~~g:~~ft:Z3 W3LCV/1 4.1,244-315-55 WlMDF 26,670-254-42 WlMXP 4,984- 89-2R WlCRP 22, 790-172-53 Wl 7PVF 4.364- 77-23 WIPGI 7,600- 81-38 WlPMY 2,074- 41-21 ~U:i~ff §:~t i~r 15- 3- 2 WlPFU 770- 2~14 WlPDN/1 WlFTJ 4.50- 18-10 'Phone WlIP ;575-- 15-10 WlLOA 16,907-160-53 'Phone WlBFT \l.5,92/i-170-61 WlHRI 18,395--142-52 WIAPK !3,158-156-43 WlGEY 7,631- 83-37 WIBAL :3,720- 60-{H W!CNX 1,872- 39-24 WlFI'J 65- ,,- 2 Rh•de Island WlLWA 100,800--627-64 W!CJH 78,275-506-62 WlLIV 59,280-456-52 WlPQM 22,790-216-/13 ~i½t~t IN~l=n~g WlBEH 2,048-- 46-18 'Phone wrnm 36,606-278--66 .12,096-127-48 your hobby or prepare ~bli'k 2,62$- 53-25 for c;a career in a radio school run WlNCX 2,424- .51-24 WIQBX }1,200- 40-22 by radio men for almost a decade. Vermont Frank Melville, W2A QK 5,669-103-27 2,525- 51-20 976- 31-16 MEL VILLE RADIO INSTITUTE 30- 5- 3 Melville Bld9., 15 W. 46th St., N. Y, 19, N. Y. Send for Bulletin "B" or call LOngacre 4°0340 6,916- 91-38 130 DEPENDABLE Turner 99 Dynamic A true professional, the Turner Model 99 Dynamic is always ready to pick up your message and deliver crisp and clear. Engineered for utmost in dependabil- ity with smooth response not affected by changes in climate, humidity, or temperature. Built-in features min imize feedback, eliminate blasting. Adjustable saddle permits semi- or non-directional . operation. Fits any standard microphone stand. Response: flat within ±5 db from 40-9000c.p.s. Level: 52 db below 1 volt/dyne/ sq. cm. at high impedance. Available in 50, 200, 500 ohms, or high impedance. Complete with 20 ft. remov able cable set. Ask your dealer. Write for Literature THE TURNER COMPANY T7th STREET, N. E. JEWEL SUPPORTS are machined and assembled with aid of precision gauging fixtures to assure perfect alignment. All ranges AC and DC available in 21/2" 3½", 4½" rectangular or round case styles and ar; fully guaranteed for one year against defect• in workmanship or material. Refer inquiries to Dept. J68. INSTRUMENT COMPANY BURLINGTON, IOWA 131 , NOR'l'HWEBTEltN W6ttAN' /l!i,400-455-M DIVISION W6DZE :H,37&--167-64 W6YOX 1 0033- 28--14 Alaal:a W6ZB$ 796-- 25--13 OFF PRESS! KL7NA 60,585-379-67 W6SBE 598-- 24--13 KL7CZ 24,168-214--57 W6ZYC 540- 18-12 KL7A'r 6,308-- 8¾-38 W6UKO 504- 18--14 KL7AF 2,020- 51-20 W6QJV• 2- 1- l 'Phone KL7NB 980- 28--14 W6MVQ Ea,t r.~~~0--680-70 KL7AW• 85- 9- 5 W6TT 85,000--1!25-68 KL7DD 40- 4-- ,J. Iaaho ;~~~K ~Uttig~~ W7ZN 73.72:1--560-66 W6NGC 37,230-292-51 W7FBD 12,256--135--37 W6TI 34,456--277-64 W7lY i,a11- 01~io W6TMP 25,250-203-50 W7EMT 2,784-- 48--'i9 W6LMZ 23,108--218-53' W6VDG 17,998-157-46 'Phone W7JL 2,438-- 53-23 Jg{?Jl }g:r&tUti2 W6EY 2 0 502-- 77-26 Montana W6KZO 2,100- 56--15 W7KVU 59,630-357-67 W6LDD 1 900- 38--25 W7FMY 35,164--299-59 0 W7EWR ;,!3,068--241-55 W6QAZ 280- 14-- 8 W7JCU 19,494-18:l--54 W6CMG 128-- 8-- 8 W7LEP 840- 24-14 W6DUB 4- 2- I W7GBL* 160- 10- 8 'Phone W7IXL 2··• 1- 1 W61KQ aa,01s--ao3--63 'Phone W6UZX 20,608--187-56 W7YLO .2,5,584-246--52 W6UPV 9.348-114--41 W7IVY 15,550-156--50 W6VEF 6.549- 86-31 W7HEM 6.696-110~31 W6DUB• 2,632- 47-28 W7LPD 753- 2.:.l-14 San Francisco W7CPY 384- 16-12 W6WNI 78.472--577-68 Or~uon W6MHF 75.375--45/i--67 W7FZA 115,834-673-69 W6WB 73.761--535-69 W7HKT 78,798--573-69 W6EvY 36,032--285-64 THE NEW JAMES KNIGHTS W7EVR 7 4. 425--465-65 W7GEB 61,425--475--65 ;g~ ¥~:~itu~¥ CRYSTAL CATALOG W7COB 57 ,984--4.53-64 W6GMF 12,760-116-44 W7DIB 3:l,170-272-62 W6lI 6,683-100-27 You'll want a copy of the new Jamea Knights catalog of W7BWD 32,550-217--60 W6MMO 5,130- 76-27 "Stabilized" crystals. It contains photos and specifica W7ECI 27,810-225--54 tions of many new crystals, crystal ovens, holders, in W7BOH 16.065-126-51 Sacramento Valley cluding new filter crystals with standard RMA pigtail•. W7JMZ 13,090-155--34 W6ZB 21,100-163-53 If your distributor cannot •upply you, write for your W7KOV :l.430- 49-28 W6REB 17,698-:192--47 W7LBV 764-- :&4-13 W6UIE !00094--103-49 free copy direct. W7ABH• 676- 20-ta W6EFM• 1,748-- 38-23 W7HBO 416- 14-13 W6GZV ,no- 16- 8 W7KEG 324- 15--12 'Phone The JAMES KNIGHTS Co. W7LNO tH7- 2lt.-li W6EOlT 21,231-171-63 W7LKD 228- 13- 7 SANDWICH, ILLINOIS W6WLI 13.056--129-51 'Phone W6VYW 5,280- 80-33 W7GUX 22.894--177-55 W6ZQD 3.810- 64-30 W7GNJ 19,500-163-60 San J oaqufn Valley W7HHH , 988-- 26--19 Washfnuton ;iiW&t iA:m::m::g~ W7GUI 88. 734--645-69 W6WI 46,662-366-66 W7KEM 78,738-597-66 W6UTU :M,500-196-50 Moss. Rudio School W6PLJ 18,169-145--51 ;mt. iu:t=g~~~ W6EUH 8,525--111-31 271 Huntington Ave., Boston IS, Mass. W7KMU .:18,050-3l!Hl2 'Phone W7KWC ·t6.400~163--64 W6QEU 60,375--353-69 W7KIH 13,130-208--56 W6lLH For over 28 years the educational radio cen W7LAR 41,229-26S-62 14,650-135-40 W7ZU 31.600-230-56 ter of New England. Prepares for all U. S. W7GHB 28,814-198-61 ROANOKE DIVISION W7A.TS 28,210-234--62 Government Radio Operators' Licenses. Also W7JC 19,580-179-44 North Carolina W7FWD• 8,663-165--21 W4KTD 75,569--500-6! gives Radio Technician Training (Pre-Tele W7LCB 6,958-127-22 W4CFL 58,800-419-56 W7ETO a,465-- 63-22 vision). Approved courses for Veteran Train W7DP :~.348-- 62-27 ;miv ~N:g::igg:gg W7DON 1,556-- 4:l--15 W4LYV• I0,764--105--52 ing under G.I. Bill. W7UWN 49/i- 2:l-- 9 1 W7LIL 375-- 26- 6 ~1E:%c -~MJ: ~J:1g Send for Catalog 'Phone 'Phone W7KRM 34.880-218-64 W4IZR 2.aoo- 4:1--2a Licensed by Commonwealth of Mass. W7BLX 14,168--162-44 W4MOEI 4.588- 74-31 W7JEO 4,921- 68-37 Department of Education W7FWR• 800- 26-16 South Carolina W7LEV 270- 12- 9 • ;~: ~:~~g: ~ti~ W4CZA 408- 18-12 PACIFIC DIVISION W4HXZ• 2- 1- I HawaU 'Phone KH6LJ 60,573-500--61 W4GVD 5.977- 7:Z-.43 ELECTB.IC.ITt'" KHllAB 13,340-150-46 W4EZF 8-- 2- >l KH6IB 400- 18--lO W4GUZ* l.'-· 1- 1 FOR RADIO AND ELECTRONIC APPLICATIONS 'Phone ONAN ELECTRIC GENERATlNG PLANTS KH6BD* 32- 4-- 4 W4KFC V(rrrt~S0-923--68 supply electric service for electronics applications Nevada W4LOX 114,973--868--67 and general uses~ mobile or stationary. Driven by W7ONO 98,000-703-70 W4KFT 100.750--62e-65 Onan 4-cycle psoline ena:ines, they are W7KEV 96.985--571--68 W4MKM 73,552-467--63 of single-unit, compact design and sturdy W7JO 19,998--195--54 W4LUE 70,136--477-59 construction. 'Phone 4 2,91:1-- 5•25 ;~x; fg:Ji&:1!tgR ONAN Electric Planta are available In W7JUO ~ W4LRI 52,635--364--58 many size• and models. .'Janta C1ara Valleu W 4,KJT 50 ,630-332-61 ALTERNATING CUR W6MUR 92.229-650-71 W4KMF 48,124-463-51 RENT: 350 to 35.000 watts W6FZW4 445,225--302--!!0 in all standard voltage11 and ;g15~ ¥H88:i!~g W 4IRZ 42,840--272-63 frequencies. DIRECT CUR W6OTI 62. 764-461-68 W4l:PC 39,772--.126-61 W4FV 37,365--282--53 R ENT: 600 to 150 000 watts. W6PBV 24.473--;ll?0-56 115 and 230 volts. BAT· W2OMC/6 21.654-201-54 W4RQR :13.920-257-53 TERY CHARGERS: .500 W6NEQ 17.100-154--45 W4KVM 29,813-268--45 to 6,000 watt.a:; 6, 12. 24. 32 W6ZGG 16,448-129-51 and 115 volts. Write for de.. W6S8A 14,291-155-37 ;t~i;r ;I:m=m=~~ W60EU 4,320- 68--32 W4IWO 19 0 665--173-.57 tailed Hterature or engi W6KJG 840- 30-14 W4BTO 19,552--208--47 neerin&' assistance. "Phone W4IUR 17,118--168-41 W6MLY 467:2 Royalston Ave. 65,540-383-69 ilfgx rn:i1tti~ii D. \\T. ONAN & SONS Mlnnelipoll• ,, Minn, (Col'!lfa'!~ on pag• 18,f) 132 2 ELEMENT 10-11 2 EL£MENT20 FOR ONLY$65!!!! WITH 2 T MATCHES HY-LITE now offers the ham a stacked 10-11, 20 mtttr rotary comblnat1on beam, built of the samt rigid, high quality, all aluminum construction that has made HY-LITE the choice of discriminating hams everywhere. The illustrated version is equipped with 2 T matches and full instructions for tuning. The 10•11 meter section can be had with extra elements at an addltlonal cost, either at the time of purchase or at any later date. (Avail• able to HY-LITE owners only.) HY-LITE Beams stacked art so constructed that a 6 meter and/or a 2 meter beam call bt stacked on top. This 11 only one of the many fine features of the HY. LITI Rotary Beams. · The 10-11 meter beam uses SA and ¾ inch telescopic elements with 1 Inch supporting tubes. The 20 meter beam uses ~• and 1 Inch telescopic tubing. and 1 inch support• ln9 tubes, The rigid, all aluminum castings are provided with lock screws and are insulated from the elements with heavy Steatite insulators. Write for further Information on this and other HY -l lTE Beams. HY-LITE~INC. Makers of fine Anlennas for AMATEUR •,FM· TELEVISION 528 TIFFANY ST., BRONX 59, N. Y. For Complete load Matching Flexibility ~- B & W SERIES "3400" .,.,, 11 ND UC TORS B&W Series 3400 Air Wound Inductors are for those discriminating Amateurs with medium power trans mitters who want the finest that money can buy in sturdy construction and electrical flexibility. Each coil has an individual adjustable internal center coupling coil. The 40- and BO-meter coils are provided with supplemental external links in series with the adjustable internal coil for roughly adjusting the load. All Series 3400 coils will match non-reactive loads from 72 to 750 ohms. , • a £ea• ture providing ample flexibility for any rig! ...... ·: ~ \ WRITE FOR B & W CATALOG ~\ , BARKER & WILLIAMSON ~ Dept.Em, 237 Fairfield' Ave., Upper Darby, Pa. 133 , W4,mY :J,990- 57-28 '.Phone W4SU 2,548- 4il---26 W4IDZ 16,874--144-59 W4CWV :J.16-- .l:t--- 9 W4MS 111, 138-131-58 W4IPS 160- g.... 8 NOW••• for The first Timel W4LFQ 105--- 7--- 6 W4KYG 63- r>- r> W4FIJ /"JeoriJtsrn-529-67 W4KSZ 41,0U4--3 Complete (§3) Rig For 6, 10, 11 Meters High-Gain Diredive Antenna With Elements, Frame and Hardware This Premax Three-Element Array pro vides in one kit ?i high-gain, directive Antenna that has"'many distinctive fea-. tures and a high degree of flexibility not usually combined in one beam Antenna. Seamless Duraluminum Elements are readily adjustable in length for operation at optimum on the 6, 10 and 11-Meter Send for descriptive circular on Rotary Beam Kit No. RB-6309 •···- or consult your Radio bands. The steel frame is designed to mini Jobber. This is an ideal, low-cost, high mize wind resistance and the complete efficiency Beam Kit that every operator in assembly weight only 30 pounds. the 6, 10 and 11 meter band needs. All elements are provided with conven iently removable shorting plates at their electrical centers, facilitating tuning and Fre1nax Products the use of alternative form of feeding as described in A.R.R.L. Radio Amateur's Div. Chisholm-Ryder Co., Inc. Handbook. 4812 Highland Avenue, Niagara Falls, N, Y. 135 WM.RV U00- 77-28 VE3S:F 32,066-241-58 VE3VZ 31,290-224-56 'Pbone VE3BLY 25,960-237-44 W5KJB 28,202-2:l9-59 VE3AVN 25.241-191-53 W5MCF 630- 19-14 VE3BOC 22,106-198-45 W5LlU 210- Il- 8 VE3AVA l!l,372-206-52 Ollahoma VE3BNA 14,670-165-41> W5LW IJJB,750-610-70 VE3DU 14,202-150-38 W,5AQE 38,812-315-62 VE3AZZ 13,360-167-40 W5EGO ]4,352-152-48 VE3ABP 12,920-1$4-34 W5IOW 9,600-120-40 VE3DR 9,418-140-34 WSGCM 5,508- 78-36 AX 8,415-101-34 W5NBN* 3,145- 37-34 7,210-103-28 W5NBZ 9:l,5- 27-14 f; 6,642-123-27 W7LGP/5 748- 23-13 MK 6,118- 86-38 2,066- 44-19 'Phone ~ l,800- 72-20 W5EHR 26,845-207-52 NB 1,564- 34-23 W5EIO 18,800-162-47 VE3BBQ• 1,538- 41-15 W5KYG 12,765-112-46 V1'13BMG - t,,!40- 60-24 W5JME 11,978-143-37 VE3BMI 1,400- 36-16 W5ERY 5,040- 64-40 VE3BAJ 412- 17-10 W5LRY 198- 11- 9 VE3BPD• 180- 10- 9 W5JCY* 8- 2- 2 'Phone South6rn Texru VE3AIB 27,675-18/i-60 W5LGG 130, 749-70 VE3AQB 26,460-210-63 W5HLK 7 474-66 VE3BDY 20,663-147-57 W5GKI 7 463-66 VE3UD l 2,250-124-50 W5LFM 1 444-67 W5GEL 72, 567-64 11,388-111-52 W,5JPC 54,000-360-60 ~tt~ 8,428- 87-49 W5FZU 44,730-321-56 Quebec WoEWZ • 44,118-393-57 \.'E2FG 4.8,870~362-54 W5FNA 41,600-320-65 VE2QB 3,5, 77,'\-270-S3 W5DAA 40,494-249-55 VB2VL 29, 768-22'l--54 W5NQI 35,981-2.5,5-,57 VE20I, 18,040-.176-41 W5DAQ 35,400-300-60 VE2GL* 702- 27-13 W5FZA 30,645-227-54 VE2WZ 645- 2:1-12 W5BTS 28,783--205-58 VE2LO 481- 18-11 W5LDU 25,819-203-51 W5NIY 24,500-140-70 JPhone W5BE 22,525-213-53 VF.2UJ 19,266-171-57 W5CXS 17,623-133-53 VE2SE 12,272-118-52 W5LBC 15,688-126-,50 Alberta W5UB 11,300-116-40 VE6AO 75,372-.~R/i-66 W5EUK 6,638- 76-35 VI,;6EO 45,293-287-66 W5ACL 3,300- 56-30 VE61lU 42, 18,5--331-65 VE60D 39,308-320-62 ;~inrtf "* Hig: ttri VE6AB 21,070-178-49 W5MIQ 900- 30-12 VR6WG la,770-135-51 W5SC 757- 2,5--14 VE6DK !0,335-I06--:lU W5KNA 384- 16- 8 YE6QS 1,317- l!l-17 W5MPE 23- 3- 3 W2'I'CP/VE6* 8- 2·- 2 '.Phone 'Phone W5KAC 88,400-240-64 VE6FK 29,504-235-64 W5FH 30,954-235--66 VE6OR 10,035-112-4.5 W51GS 26,933-171-63 VE6PY 4,932- 72-36 W5BDI 17,385-143-61 W5LHJ 13,120-161-4] , Brltlsh ColumUa W5MTA 12,432-148-42 VE7ZM 8,5,818-505-69 W-~NKY 2,938- 48-25 VE7ALE 65,650-404-65 1,188- 44-27 VE7EH 52,416-414-63 will be paid for exclusive informolion resulting in purchase of ~ng,w. 18- 3- 3 VE7IQ_ 41,738-26\1-63 surplus parts or equipment. VE7XA 30,000-250-48 , NewMIZ'fco VE7ACS• 20,638-218-48 If you know of any quantities of good, new surplus available in W5NID 41,745-381-55 VF.7 AC 16,830-165-51 your Lab"' shop, factory, etc., rush full details to our Buyer of- WllFEA/5 28,532-208-55 VE7CE 1,5,510-141-44 WMFll 27,267-224-61 VE7FG 12,16:1-140-35 W5VN 9,204-117-39 VE7ARP 10,500-108-40 HARRISON SELECT SURPLUS WSJYW ,5,280- 66-32 VE7JO 9,500-100-38 10 West Broadway• Phone, BArclay 7-9854• N.Y. 7 W5KWP ·1,950- 60-33 VE7CU 7,425- !19-30 W5KWR 3,300- 55-30 VE71JI n, 400- 72-30 W 5HJF 198- 22- 9 VE7OK ll,325- 70-19 VE7ABQ 2,719- 4,5---25 CANADA VE7JD 2,610- 58-18 VE7RU 2,156- 38-2:~ COMMERCIAL RADIO INSTITUTE Marlttme VE7AFI 2,048- 63-13 VElTR 70, 784-5.56-64 YE7AER 640- 35-10 VElKJ 51,910-358-M A RADIO TRAINING CENTIR f OR 12 8 YIARS 45,012-841-66 ':Phone ~mi 25,041-250~51 VE7ARH 12, 7 40-10 4-49 Re1ldent Cour•es Only • Broadcast, Service, Aeronautical, Televf VElCU 23,575-205-46 VE7VO 3,443- 52-27 ston, U.H.F., Preparatory Course. frequency Modulation and Marine VElEK 20,212-194-42 V1'J7ALM :l,100- 51-25 telegraphy. Classes now forming for Summer term June 1st. Entrance VElDB 12,432-150-42 VE7IM 972- 27-18 examination May 17th. VElIM 11,385-127--36 VE7AET• 2- 1- I VElTF 8, 450- 88-40 VE7WL* 2- 1- J Literature upon request. Veteran training VElRG 4,277- 60-29 VElFB• 2,418- 47-26 Yukon Dept. B, 38 West Biddle Street, Baltimore 1, Maryland 960- 24-16 VE8AY 34,272-275-63 ~½~ 23- 3- 3 'Phone 'Phone VESAK* 24- 4- 3 EASY TO LEARN CODE V1'11QZ 1,785- 34-21 Manitoba VElDQ* 8- 2-· 2 VE4AM 8,483- 87-38 VElCE 5- 2-- 2 lt i1 easy and pleasant to team or increase Y.F.4PK 2t-1~ .speed the modem way- with an lnstructo.. VElMZ .... 2- 2 VE4NX l,3tt VE4CA 63- 5- S 0 Ontario VE4WE 2- 1- 1 t;fn1!er °o~e al:~~r. s~~C:!i:ntA fo~ui~\~ VE3KE 9(1,050-567--68 practical and dependable method. Available VE3EF 75,040-561-67 'Phone t.apes from beginner~.& alphabet to typical VE3EK 7 4,370-444-67' VF.4RP 20,518-142---58 messages on all subjects. Speed range 5 to 40 VE3GT 61,840-390-64 VE4YO 16,448-129-64 WPM. Always ready, no QRM, beats having VE3AEM 59,875-481-/lo l!lOmeone send to you. VE3AGX 55,957-415-54 Sat"'cllewan VE3AHV t.2,227-417-63 ENDORSED BY THOUSANDS I VE3JJ• 50,873-357-57 fiiJ~~ fUM=~~~~ VE3BBR 50,530-329-62 VE5QZ 33,016-219-61 The InatructoQrapb Code Teacher liter VE3ACB 47,973--311-62 VESCO :l!,392-220-58 ally takes the place of an operator-instructor VE3AWE 47,430-372-51 VE/iMS 16,675-154-46 and enables anyone to learn and masiter oode VE3ANO 41,753-294-57 VE5RR 7,515- 84-36 without further assiatance. Thousands of suc VE3BHX 37,088-322-46 VE5KJ• 75- 6- 5 i::essful operators have "a<.-quired the code" with the Inatructol1raph VE3MI 'Phone Syatem. Write today for full particular• and convenient rental plans. VE3AJP ~tm::i~i VE5MWI• 196- I:l- 6 INSTRUCTOGRAPH COMPANY ' W3KUY 4 opra. • Rq. staff members not eligible for a.wards. • Two opra. • W eat Side Radio Club •1 Seven opra. '709 SHERIDAN ROAi>, CWCAGO 41, ILLINOIS • W6HJT operator, 136 Uaw I BIG RECEIVER QUALITY ffV • in the LOW-PRICED FIELD! THE NEW NATIONAL NC-33 9 5 $ 6 5 Amateur Net • Operates from 110-120 volts AC or DC, Ideal for ship board and other uses where DC only h available. • Electrical bandspread on all bands! Broadcast, amateur, police and foreign bands plainly marked. • A real communication receiver covering all frequencies from 500 kcs to' 35 mes. POWER SUPPLY SPECIAL 1 Plate transformer 660-550 V. @250 ma. • I Filament transformer 5 V., $ 249 5 3 amp. • 1 Swinging choke 4-16 Hy. 250 ma. • 1 Smoothing choke 10 Hy. 250 ma. • 1 RK 60 rectifier • 1 Socket • 1 Chassis (undrilled} complete 816 POWER SUPPLY SPECIAL 1 Plate transformer 660-550 V. @250 $ S ma. • 1 Filament transformer 2.5 V., 9 5 amp. • 2 816 tubes • 2 Sockets I • 2 Platecaps 9 comp ete IMMEDIATE DELIVERY FROM STOCK WHOLESALE RADIO PARTS DIVISION · SPORTING GOODS COMPANY M & H 512 Market St., Philadelphia 6, Pa. •-•-·-·-·-·-·-· 1 ALUMINUM •I YOU WANT EM ... CALL PLATES I Your call cast In alwninum • UNIVERSAL'S GOT 'EMI I and polished 1¼" letters. Plate size y,!tgy J'~r.~3 ~;'i~u~~ l Brand new FT 171 B j ~~tP~~~~f~~g, L for car license and D for desk use. $1.75 I e P & H SALES CO. • CRYSTALS I 619 .Jasper St. Kalamazoo 31, Michigan I WHILE THEY LAST ·-·-•-•-•-·-·-•-•-•-•-•-•-•-•-· 99/EACH PREPAID CASH WITH ORDER 3510 - 3580 - 3945 3955 - 3995 KCs UNIVERSAL RADIO SUPPLY CO., INC. 715 South 7th Street • Louisville 3, Kentucky ,------1 SHOOTS TROUBLE FASTER I I MAKES MORE MONEY FOR YOU ON JOB OR AT SERVICE BENCH! •. ··.. I & In radio service work, time means money. I • 1 'I. .... ~:1~:!.,tr:;~:J.a~;i, ~h:~~~~_:t~l.'~:e~ I trouble shooting tool, SIGNALmE has no ------~~r:na~B1,1,e-.. _ equal. Merely plug In any AC or DC line, I - ""'ll'-- ---:&- start al speaker end of circuit and trace back, I MULTl-FREQUENCY GENERA TOR stage by stage, listening In set's speaker. Generates RF, IF and AUDIO Frequencies, I at distributor or post- 2500 cycles to 20 Megacycles, Also used for I $ 9 9 5 paid, direct, Sorry, no checks on Sensitivity, Gain, Peaking, Shield• C.O.D.'s. Ohioan'• Ing, Tube testing. Wt. 13 ez. Fits pocket or I - add 3% State Sales tool kit. See at your distributor or order I Tax. direct. I CLIPPARD INSTRUMENT LABORATORY, INC. I Dept. T, 1125 Bank Street, Cincinnati 14, Ohio I Quall/led Jobbers write, wire for details , I ------~137 r HIRE:S MORI FOR itYOUR MONEY ttl~eH tc« 6u, lr ~ w,eH tcu t1«11t/e TRADE-IN 0' v:- .•,•,•········:·············:·•·····································--··············•:;:Getting far more for your :::: FEATURE 2: used Communication equipment :::: 0'F THE means paying much less for the ;::: new! That's the important, ::;: MONTH ❖: money-saving advantage in :;:: HAMMARLUND'~ ;:;: dealing with Walter Ashe. Cash ::;: HQ-129X :::; in now on the bigger-than•ever ::!: S 3· 0 t allowances offered·· by _Walter mi COMMUNICATION RECEIVER ___ .. only 17 7 :::: Ashe on your used equipment. :;:: EAKER IN MATCHED CABINET ONLY $11.85 t\ Wire, write, phone or use the :;:; SP ------···-- -- :,;, handy coupon below. :;:: This deluxe Hammarlund Receiver can now be yours at a substantial saving on a .-.,. .. ·:··:···:···•···············•· • • • • • • • • • • • ••• ·•·•·•"' • • • • • ·;. •• Walter Ashe Trade-In deal. FILTER CHOKES SURPLUS TUBES-WHILE THEY CARBON1 4.5 Hy. X 150 Ma .. 70 Typ~:.~~~an~~ike. LAST-NEW-IN CARTONS ohms Res. #5269 Shpg. S. B. carbon wit h $ push-t.o•talk switch 3AP1 . $1.96 807 .... 1.13 on hand I e. Brand 5R4GY .75 809 1.45 [] new. Shpg. Wt_ 3 lbs. 5BP1 t.96 811 1.95 .;:::~::;:~~:.!~: ONLY 6 9c 5BP4 .. 1.96 813 5.95 6AK5 .90 814 4.50 Dual 12 Hy. X 200 Ma., TRANSMITTING KEY 24G .... l.10 815 2.25 15 0 ohms ·Res. per sec Type J-37. Large VT-127A 2,95 829B .. 3.00 tion. #2.785 Shpg. Wt. coin silver con• VR-105 .75 872A . . 3.00 tacts. Shpg. Wt. VR-150 . .75 2 lbs. ~If ~n;:~: ...... s4.95 Only 98c DON'T FORGET! I HEADPHONES Walter Ashe is headquarters ohms4 Hy. Res.X 300#63 17Ma., Shpg. 40 Type HS - 16A. 2000 for "Good-as-new," recondi• • · Wt. 13 lbs. o h m s impedance. Canvas W e b head• tioned communication equip band, and long stan~ ment. Look at the following ...... Only.. _...... $4.95 dard type co r d . typical <'Kamples of money •••f~•;f:•' •:~•= ','.'-'M•,:: Shpg. Wt. 3 lbs. saving bargains. (Space doesn't permit fisting them all!) 8 Hy. X 500 Ma., 55 ohms Res. #8056 Shpg. Hallicrafters Wt. 18 lbs. S-40 ...... only $ 57.50 Hallicrafters SX-25 ...... only $ 89.50 Only...... ___ SJJ.85 National NC-173 R ~dE Spkr. only $149.00 l.,l,•2c!!!!!!!!llL------1 VHF-152 .. only $ 67.50 (Quautities limited on FILTER above itPms) S~•nd I'l'or Complete List. CONDENSERS REMEMBER ..• Jm1r :, Mfd. X 400 VAC. Trnrfp.Jn'R worth rnorf:i ut Good for a b o u t the Walter .\she ,;tore. For 15 oo voe. Shpg. real monE'yDsa\'ing get "\\"'.al Wt. 3 lbs. ter .A.she's offer be.fore you make tJ:utt trade. Only______gac DYNAMOTOR Get Your Free C-Opy 6 or 12 VDC Input. 500 VDC at 160 .Ma. out- of Our Latest Catalog 2 Mfd. X 2500 put. Brnn QSLSI Quality cards priced right. Samples. BEAM rotators, pro peller pitch. changing mechanisms. Descriptive shf!et free,. \V9UTL. 1768 Fruitdale, Indianapolis, Ind. WANTED: Beat Kw transmitter $1000 will buy. Prefer factory built job but will consider good custom job. For somethil!,& really excep HAM-ADS tional and a ban~-ain, will pay up to $1500, Please no runk, but if you have something really good, \\Ti.te W7 ALO-. Route 4, Box 336, (1) Advertising shall pertain to radio and shall be of Salem, Oregon. nature of interest to radio amateurs or experimenters in their punmit of the art. \VANTED: old wirelesi:t gear from 1905 on up. State condition, (2) No .display of any character will be accepted, nor c.an price, details. \\'!CPI. any special typographical arrangement, s1lch as all or part QSLs. Design your own, at regular price. Plastics, Bristol, suede capital letters be use SEl.. L National 100XA amateur receiver, ct'ystal. prec1a1on dial, BC-348 E.H.K.L.M.O.P.R.S owners. Plans and scliematic for 10-160 meten. First $6U takes it. W2DRU. 1535 Wildwood Ave., changina- 200-500 Kc band for 10-meter operation. $2.00 or we will Camden, N. J. 0 t t£ 1a~rsJ?rrJti;~~n~~iii!cYfoP~Cjih~i~tk~o:. ~~~;y:ii;.b~k~ua er SELL: 100-watt bandswitching phone/cw transmitter, complete on one chassis and panel, with crystals and crystal mike; has TZ-40 N. Y. HAMS: 18 Ft. wood lattice tower, 2 sections. with 20M ladder final and HY31Z modulator, $135. Seven watt cHpter speech ampli boom. $20.00. Also Sonar XE-IO, almost new, $25. 1''.o.b. W2NCL, fier complete on 5¼" relay rack panel and chassis with crystal 478 81st St., Brooklyn, N. Y. mike, $40.00. One BC-221 (Bendix) complete with built-in power SURPLUS: Deluxe CrYstal finishin11 kits containing holders, Quartz blanks, abra.qive, etching fluid, complete instructions. Only frw ~¥ff1Yi:ut:·\l:~-iP."~~~~~;fottl,1~;1nt~.;i~~;k':"8. one new ~i:,~;:~yl~~.:tM;?Rrr;,<;,~,rl.ostpaid. Formerly sold $8.75. Veoto SELL: Hallicrafters S-40, perfect condition, fuse, recording outlet, earphonea. Best offer. Blane, 15 No. Mayfield, Chicago, Illinois. I-'OR Sale: One BC-610 converted, $600; one BC-312N complete, (k,J~~i!~ 72\W!ffsfX;;e~e:rs~g:~~a:~'N3:11~ _or both receiven. J. D. N3l;J;'J.~Psf·j~ii!-!5ila~:~';1it~o~.1T.r $11 less power supply, 8~6~i~;\W, R.f~!~Y, low in price. Colonial Press, 22 Jackson St.• FOR Sale: Collins 310B exciter, complete. W!iTWX. SELL: 1'emco 7'"s:.:;G:::A::...,li_k_e--n-ew-s-·o_n_ar_X_'~E--l-O~an-d_B_c~·,_-2~2-1,-$~S~O'"O,-.-Alcc---so SELL BC-348O bought new and used three months, converted a/c, S meter, speaker in National cabinet, $60. Sell new one KW {"{.¾2:i-h·,82f.t!~ .f'§'t:'!et~uJG:y~~~ct':"I<'i'i~ptor, $250.00. F.o.b. RCA modulation transformer. $10. A. Bateman, 429 Achille Rd •• SELL:6-, 10-, 11-meterconverter (RME DM-36, modiftedperQST). Havertown, Pa Excellent condition $40. WtFTX, R.F.D. 1, Granby, Conn. SURPLUS: HK-454H, $9.95; four 6C21 mfg. by 1'~imac and G, K MODiJLATION transformer: Ideal for thaCKW rig. Ha• all popu- •im!lar to 750TH, $14.50 ea. National tank cond. 100 ""fd, 9000v. 1ar impedance matches. Sell or trade for ART-13 xmttr. Gus Kara S7,50, Johnson tank cond. 100-100 µp.fd. 11,000v. $7.50 (used). JOW, 5-174 Shangri La Dr., South Norfolk, Va. F. Gartrell, Westminster, Maryland. NEW Mark II transceiver 40-80 meters, spares diagram dynamotor, SELL: 1941 Meissner Deluxe shifter. 40-80-20 coils. No reasonable $40. W!IVHM, Winterset, Iowa. offer refµsed. You pay shipping. Trueblood, 1301 Mass. Ave., N. W., FOR Sale: 1 Kw phone and "c~w~1~0~-..,8~U-m_e_te_r_b_an_d~tran--•-m""'i-tt_e_r_ Washington, D. C. 8 ~~':i~to~~ilit b~~ng~n~:~~ r!~~ilte~P4-;,s~df~~~l fcf r!!t~ SELL: HQ-120, 170 W. remote c. phone transmitter, speeeh ampfl. Rig contains J Variacs 8 meters and overload relays. Will deliver and mike. $190.00. W6DZL, and set up free within 100 miles of N. Y. C. Photos and description sent on r~quest. Best offer takes it. William H. Vo,iel, jr., W2MYE, QSLS-SWLS. Highest quality. C. Fritz, 1213 Briarl[ate, Joliet, Illi 51-01 39th Ave., Lon11 Island City 4, N. Y. nol•• SELLING out: One late model HR0-5 $250.UO; Hallicrafters HT-9 transmitter, 3 aets of coils and extra tube, latest model $300.00i National 600-watt transmitter $750.00. All in excellent condition. WjSYK, 1137 Terrace Drive, Richmond Heights 17, Missouri. FOR Sale: BC-610, excellent condition. $600.00. W8KUW, 138 Vernon, Ashland, Ohio. SELL 750-watt CW, 400 watt fone transmitter, $500. QSTs, 1926 WANTED: A communications receiver in good condition, ~ason t~xrl fgfRu!~1i K~~~il-!::i':a~:.EN. }'.44 throu11h 1947, $20. able. \Vm. H. Paul, WlNTL, 8 Laurel 8t., Boston, Mass. QSLS~ SWLS. For distfnctive eards, write McEachron, 1408 Brent ~~~Ii'J~t~~i!gc~~tit·c&u!~~a~1s r:rwio~:!~t:31 ;~~er~~~b~~:: wood, Austin, Texas, for eamples. Perfect working order -- $800. W8YMO, 1020 Main, Mount .Pleas ant, Michigan. TRADE or sell: RCA transmitter; phone-CW, 500 watts, 80-40-20 HRO - Late pre-war relay rack model. ham coils and power supp~, meter bands. Want photoaraphlc equipment or $300.00. Kenneth Lundy, 414 W. Lorance, T'yler, Texas. ~Jf B:~~tr~n~~~~·i~~ia~ffcfa.James G. Stradlinlr, jr., W4KR ~ CRYSTALS: Fine commercial units for SCR-522'•• Police, Taxi, F The No. 92101-Antenna · Matching Preamplifier The Millen 92101 i• an electronic impedance ttlatching device and a broad-band pre- fuf,:~~ p;r~~\I;iorm::er:tii~~I~ 6u:::!J to meters. Coils for the 15 and 20 meter bands as well • $ television <•hannel 2 thru 6 inclusive nho available, Thin unit is the re sult of combined engineering- efforts on the part of General Eledric Company. and the ~lames Millen Manufacturing Company, The No. 92101 is extremely c.ompact, the C-a5'1! measuring only 6,tt" x 5'%~' :ii. 3n, The Sangamo Eledric Company ...... , ...... Hl band changing inductor unit p(uga into the Si.gnal Electric Manufacturing Co•....•..•....•... 124 <•pening- in the front of the panel. .Plug is Silver Company, McMurdo ••• i •••••• ~ ••••••••..• 105 Sonar Radio Corporation. , . , ...... 143 r:~~~:tAfKS :~b~r;:'o~ ~h':e:ecci~~-r<~=~;i Standard Radio & Elec.. Products Co,. 110 connectors and plugs a.re furnh1hed for the Standard Transformer Corporatidn .... 144 antenna and receiver connections. ~tt=inbergs .•... , .....•. , . , .••..... 106 Sun Radio of Washington ..... 127 113 +~~~l~O~ag~i:'.~r~~~~t~~~: :: : : ~ :: : : : : : : : : : : : : : ~ 131 JAMES MIL(E'Jit: \talparai-!fo Technical Institute .... , . , ...•...... 1-14 0 134, M F9~· : Victor A. Bl~e, Prince George, B.C.-On April 17, 1948 Vic re ceived a Q5S3 report in a QSO with VK2AFE in Sidney, Austra lia, 7329 Miles. Besides Japan W2l'UPS Vic has all the districts in U.S. Arnie Peterson, Newark, N. J.-Arnie is the with many Q5S9 reports. Vic is tough one to beat with 11 countries to date. pictured with his set up ii. the Arnie believes he is the only Mobile station car, a 6 mtr and 10 mfr combi to work a DX Mobile both in motion. South nation. What's new on 6 Vic? Africa is his claim to distanc•·- Arnie works most of his mobile in motion. These are only a few satisfied users of the SONAR NBFM Mobile Transmit• ter, MB-611, The excellent mechanicol and electrical engineering of this compact, rigid transmitter, makes it an ideal unit for the car, trailer, boat, plane, summer camp, shack and many other enjoyable applications, Using the exclusive SONAR Phase Modula• tion circuit and a highly efficient pi-network antenna matching system, the MB-611 makes available 30 watts to any type antenna or as a driver to that high-powered rig at home. Contact the mony users of MB-611's on the air or see them at your favorite dealers, NOW. Write us for literature on this and the other fine products of SONAR. 0 XTAL AND $,2~s?POWER RADIO C .. HB-611 . SUPPLY ' 0 RP UIPMENT .• XE 10 • VFX 6 59 MYRTLE AVE ., B'KOLYN R l, A N.Y. T I O N 80 • MB 611. • CFC • SRT 75 143 , 1 1 STANCOR'S I ST-203-A --- - Mobile Transmitter Kit HE STANCOR'S ST-203-A is a compact, versatile trans T mitter designed primarily for mobile operation, but also useful for fixed station service. You can operate the ST-20 3-A in IN YODR CAR your car, then quickly transfer it for use in your shack, summer home or other fixed location. Special mounting fasteners make the ST-203-A quickly transferable from car to fixed station. Power is obtained from a dynamotor or 'fibrator supply for mobile work or from an AC supply at a fixed location. Performs efficiently with the surplus PE-103-A dynamotor and a T-I 7B carbon microphone-. Briefly, the circuit lineup consists of a 6V6 harmonic oscilla tor working from 7 me. crystals, a 2E26 Class C amplifier, a 6J5 grounded-grid speech amplifier, and a push-pull 6V6 Class A-1 modulator. IN YOUR SHACK Attractively styled in silver-gray hammertone finish with gray plastic control knobs and brushed metal carrying handle. Size only 8 ¾" x 7 %" x 6 ¾", Weight with tubes and crystals, 9 ¼ pounds. Kit includes prefabricated chassis, mounting plate, dust cover, prepared lead wires, all constructional components, and detailed, illustrated instruction $4470 manual. AMATEUR NET PRICE, less accessories ... AT YOUR SUMMER HOME NOTE THESE FEATURES: • 27.5 Watt Amplifier Plate Power Input • · Pr•H•to-Talk Operation • Radlotelephony-Amplltude Modulation • Both Mobile and Fixed Station Use • Acceuorles Available at Low Cost • Two Crystal-Controlled Frequencies • Compact-Lightweight • Covers Popular 10 and 11 Meter Bands e Moderately Priced SEE THE ST-203-A KIT AT YOUR STANCOR DEALER TODAY OR WRITE DIRECT FOR DESCRIPTIVE BULLETIN . STANDARD TRANSFORMER CORPORATION 3574 ELSTON AVENUE • CHICAGO 18, ILLINOIS 144 PRINTED IN U.S.A. '' JIUMP'ORD p,ra;sa CONCORD. N. ff, • the national HFS Enjoy amazing VHF reception made possible by such summer phenomena as temperature inversion, sporadic E. Get a National HFS and take it with you on vacation and week ends. Check MUF and be ready for those 6-meter DX contacts while pleasure-bent high in the hills! Designed for mobile and portable use, as well as fixed operation, the HFS is ideal for both your car and your shack! • COMPLETE COVERAGE! 27 mes to 250 mes in 6 bands. AM-FM-CW! Operation assures optimum signal-to-noise ratio. • MOBILE-PORT ABLE-FIXED! National 686S vibrator supply - 5886 power supply- or "A" and "B" batteries. • RECEIVER OR CONVERTER! Makes features of con nected receiver usable on VHF! $125 (power supply extra) • See your Notionol dealer listed in the classified section of your 'pho11e book • { j,,,,, I ' Grid Bias Mox. Mox. Power Max. Calcu• Max. Plate Screen Output freq. lotor J Max. Max. Mox. Mox. Max. Grid Dissi- Dissi- (watts) in Mc. Factor Tube Plate Screen Grid Plate Screen Ma. potion potion (approx.) Type volts volts volts Ma. Ma. (Note l) (watts) (watts) (Note 2) (Note 3) (Note 4) ( f RCA-6AG7 375 250 -75 30 9 5 9 l.5 7.5 30 22 RCA-6AK6 375 250 -lO0 15 4 3 3.5 1 4 60 9.5 l RCA-6(4 300 -lO0 25 8 5 5.5 60 18 i RCA-6F6 400 275 -100 50 ll 5 12.5 3 14 30 1 RCA-6L6 400 300 -125 100 12 5 21 3.5 28 30 8 RCA-6N7 350 -100 30 5 5.5 14.5 30 35 ! (per (per (per (total) plate} grid) plate) RCA-6V6GT 350 250 -100 47 7 5 8 2 11 30 9 Note l: l 00,000 ohms maximum grid resistor Note 3: Maximum frequency for full power output and input \'6.te 2, Based on 70 % plate efficiency Note 4: For pentodes, this is the grid-screen amplification factor Plenty of R-F power ~~~ with RCA Receiving Tubes These seven RCA receiving tubes are tops for r•f drfrer app cations in amateur transmitters. • Just take advantage of the new increased high For the full story on how to use the ratings frequency cw ratings for the seven popular RCA your particular application, see Ham Tips, No, receiving types, listed above. These ratings are Dec. 1946. If you do not have a copy, ask yo your guide to even greater receiving-tube per RCA Tube Distributor, or write RCA, CommE formance and maximum life in r-f service, such cial Engineering, Section FM-54, Harrison, N. as crystal oscillators, buffers, doublers ••. and low-power finals! *Absolute maximum ratings/or amateur use exclusfre~y. THE FOUNTAINHEAD OF MODERN TUBE DEVELOPMENT IS RCA TUBE 1'EPARTMENT RADIO CORPORATION o, AMERICA HARRISON, N. J.